Answer:
(D.) No, because polar covalent molecules have stronger intermolecular forces than nonpolar covalent molecules.
Explanation:
In water molecules intermolecular hydrogen bonding occurs between hydrogen and highly electronegative elemnt oxygen that increases the intermolecular forces. Hence water has high boiling point.
Answer:
D. No, because polar covalent molecules have stronger intermolecular forces than nonpolar covalent molecules.
Explanation:
Hello,
Intermolecular forces are those which attract or repel molecules to, or from each other. In this case, since water is the involved molecule, it is known that it is a polar covalent one, as the difference between the electronegativities of oxygen and hydrogen is 1.24, in this manner, it is also known that the more polar the molecule is, the stronger its intermolecular forces are are they are tend to stick the molecules. In such a way, the answer is: D. No, because polar covalent molecules have stronger intermolecular forces than nonpolar covalent molecules.
Best regards.
Watch the animation and select the interactions that can be explained by hydrogen bonding. Check all that apply.
a. CH4 molecules interact more closely in the liquid than in the gas phase.
b. HF is a weak acid neutralized by NaOH.
c. Ice, H2O, has a solid structure with alternating H−O interactions.
d. H2Te has a higher boiling point than H2S.
e. HF has a higher boiling point than HCl.
Answer:
c. Ice, H₂O, has a solid structure with alternating H−O interactions.
e. HF has a higher boiling point than HCl.
Explanation:
For molecules to interact through hydrogen bonding, it is required that there is an H atom bonded to a more electronegative atom, such as N, O or F.
Select the interactions that can be explained by hydrogen bonding. Check all that apply.
a. CH₄ molecules interact more closely in the liquid than in the gas phase. NO. The electronegativity of C is not high enough to form hydrogen bondings.
b. HF is a weak acid neutralized by NaOH. NO. This reaction occurs in water and it is better explained by ion-ion forces.
c. Ice, H₂O, has a solid structure with alternating H−O interactions. YES. This structure is a consequence of the hydrogen bonding.
d. H₂Te has a higher boiling point than H₂S. NO. The electronegativities of Te and S are not high enough to form hydrogen bondings.
e. HF has a higher boiling point than HCl. YES. The stronger hydrogen bonding interactions in HF explain the higher boiling point.
Final answer:
Hydrogen bonding explains interactions such as HF being a weak acid, the solid structure of ice (H2O), and the higher boiling point of HF compared to HCl.
Explanation:
In the context of the provided information, the interactions that can be explained by hydrogen bonding are:
b. HF is a weak acid neutralized by NaOH.c. Ice, H2O, has a solid structure with alternating H-O interactions.e. HF has a higher boiling point than HCl.Hydrogen bonding occurs when a hydrogen atom is bonded to a highly electronegative atom such as oxygen, nitrogen, or fluorine, creating a strong dipole-dipole interaction.
These interactions are responsible for the higher boiling points and particular properties of substances like water (H2O) and hydrogen fluoride (HF).
Water alone does not easily remove grease from dishes or hands because grease is nonpolar and water is polar. The addition of soap to water, however, allows the grease to dissolve. Study the structure of sodium stearate (a soap) and describe how its structure allows it to interact with both nonpolar grease and polar water Drag the terms on the left to the appropriate blanks on the right to complete the sentences. Reset Help The soap molecule has a nonpolar and a polar cationic end when it is dissolved in water. When it dissolves in water, the sodium stearate congregates to form small spheres (called micelles) with the on the inside and the on the surface. The anionic end can attract and interacts with the polar water molecules, while the interact with the nonpolar grease. This allows the soapy water to remove the grease by trapping the grease inside the micelle.
Answer:
Micelle Formation
Explanation:
The soap molecule has a nonpolar and a polar cationic end when it is dissolved in water. When it dissolves in water, the sodium stearate congregates to form small spheres (called micelles) with the on the inside and the on the surface. The anionic end can attract and interacts with the polar water molecules, while the interact with the nonpolar grease. This allows the soapy water to remove the grease by trapping the grease inside the micelle.
Because greased is electrically neutral and water is polarity, water alone will not simply remove oil off dishes or hands. The grease, on the other hand, dissolves when soap is added to water.
This traps the greasy within the micelle, allowing the soapy liquid to remove it.
So,
In case 1: Hydro-carbon
In case 2: Anionic
In case 3: Hydro-carbon
In case 4: Anionic
In case 5: Anionic
In case 6: Hydro-carbon
Learn more:
https://brainly.com/question/5214674?referrer=searchResults
Based on the reduction potentials listed in the textbook appendix, which of the following redox reactions do you expect to occur spontaneously?
W. 2Al(s)+3Pb2+ (aq) → 2Al3+ (aq)+3Pb(s)
X. Fe(s)+Cr3+ (aq) → Fe3+ (aq)+Cr(s)
Y. Ca2+ (aq)+Zn(s) → Ca(s)+Zn2+(aq)
Z. 2Cu+(aq)+Co(s) → 2Cu(s)+Co2+ (s)
a. W only
b. X, Y and Z
c. Y only
d. X and Z
e. Z only
f. X and Y
g. W, X and Z
h. X and Y
i.W and Z
Answer: The redox reactions that occur spontaneously are Reaction W and Reaction Z.
Explanation:
For the reaction to be spontaneous, the Gibbs free energy of the reaction must come out to be negative.
Relationship between standard Gibbs free energy and standard electrode potential follows:
[tex]\Delta G^o=-nFE^o_{cell}[/tex]
For a reaction to be spontaneous, the standard electrode potential must be positive.
To calculate the [tex]E^o_{cell}[/tex] of the reaction, we use the equation:
[tex]E^o_{cell}=E^o_{cathode}-E^o_{anode}[/tex] .......(1)
Substance getting oxidized always act as anode and the one getting reduced always act as cathode.
For reaction W:The chemical reaction follows:
[tex]2Al(s)+3Pb^{2+}(aq.)\rightarrow 2Al^{3+}(aq.)+3Pb(s)[/tex]
We know that:
[tex]E^o_{Al^{3+}/Al}=-1.66V\\E^o_{Pb^{2+}/Pb}=-0.13V[/tex]
Calculating the [tex]E^o_{cell}[/tex] using equation 1, we get:
[tex]E^o_{cell}=-0.13-(-1.66)=1.53V[/tex]
As, the standard electrode potential is coming out to be positive. So, the reaction is spontaneous.
For reaction X:The chemical reaction follows:
[tex]Fe(s)+Cr^{3+}(aq.)\rightarrow Fe^{3+}(aq.)+Cr(s)[/tex]
We know that:
[tex]E^o_{Fe^{3+}/Fe}=0.77V\\E^o_{Cr^{3+}/Cr}=-0.74V[/tex]
Calculating the [tex]E^o_{cell}[/tex] using equation 1, we get:
[tex]E^o_{cell}=-0.74-(0.77)=-1.51V[/tex]
As, the standard electrode potential is coming out to be negative. So, the reaction is not spontaneous.
For reaction Y:The chemical reaction follows:
[tex]Zn(s)+Ca^{2+}(aq.)\rightarrow Zn^{2+}(aq.)+Ca(s)[/tex]
We know that:
[tex]E^o_{Ca^{2+}/Ca}=-2.87V\\E^o_{Zn^{2+}/Zn}=-0.76V[/tex]
Calculating the [tex]E^o_{cell}[/tex] using equation 1, we get:
[tex]E^o_{cell}=-2.87-(-0.76)=-2.11V[/tex]
As, the standard electrode potential is coming out to be negative. So, the reaction is not spontaneous.
For reaction Z:The chemical reaction follows:
[tex]Co(s)+2Cu^{+}(aq.)\rightarrow Co^{2+}(aq.)+2Cu(s)[/tex]
We know that:
[tex]E^o_{Cu^{+}/Cu}=0.34V\\E^o_{Co^{2+}/Co}=-0.28V[/tex]
Calculating the [tex]E^o_{cell}[/tex] using equation 1, we get:
[tex]E^o_{cell}=0.34-(-0.28)=0.62V[/tex]
As, the standard electrode potential is coming out to be positive. So, the reaction is spontaneous.
Hence, the redox reactions that occur spontaneously are Reaction W and Reaction Z.
Example: Serum containing Na gave a signal of 4.27 mV in an atomic emission analysis. Then, 5 mL of 2.08 M NaCl were added to 95.0 mL of serum. The spiked serum gave a signal of 7.98 mV. Find the original concentration of Nat in serum.
Explanation:
It is known that,
No. of moles = Concentration × volume
As 5 ml of 2.08 M NaCl NaS added to 95 ml of serum then,
Total volume = (95 + 5) ml = 100 ml
Therefore, total moles of [tex]Na^{+}[/tex] = (5 × 2.08) + (95 × x)
where, x = concentration of [tex]Na^{+}[/tex] in original serum
Hence, signal obtained for this NaS = 7.8 mV
Let us assume same volume, that is, 100 ml Serum then [tex]Na^{+}[/tex] will be (100 × x) mol.
Signal obtained for this is 4.27 mV.
Now, the ratio of signal is equal to the ratio of mole.
So, [tex]\frac{4.27}{7.98} = \frac{100x}{(5 \times 2.08) + 95x}[/tex]
x = 0.113
Thus, we can conclude that original concentration of [tex]Na^{+}[/tex] in Serum is 0.113.
The original concentration of Na+ in serum is found by using the provided signals before and after spiking with NaCl, identifying the change in signal due to added Na+, and back-calculating to find the initial Na+ level in serum. The calculation reveals that the original concentration of Na+ is approximately 0.126 M.
Explanation:To find the original concentration of Na+ in serum, we use the information provided by the atomic emission analysis before and after spiking the serum with a known amount of NaCl. We are given that the unspiked serum produced a signal of 4.27 mV and the spiked serum produced a signal of 7.98 mV after adding 5 mL of 2.08 M NaCl to 95.0 mL of serum.
Step 1: Calculate the moles of Na+ added from the NaCl solution.
Moles of NaCl = 2.08 mol/L × 0.005 L = 0.0104 mol
Step 2: Since the reaction of NaCl in water leads to one mole of Na+ for every mole of NaCl, moles of Na+ added = 0.0104 mol.
Step 3: Calculate the increase in signal due to the added Na+.
Signal increase = 7.98 mV - 4.27 mV = 3.71 mV
Step 4: Determine the signal per mole of Na+ added.
Signal per mole = 3.71 mV / 0.0104 mol = 356.73 mV/mol
Step 5: Calculate the original moles of Na+ in serum from its signal.
Moles of Na+ in serum = 4.27 mV / 356.73 mV/mol = 0.01196 mol
Step 6: Calculate the concentration of Na+ using the serum volume.
Concentration of Na+ = 0.01196 mol / 0.095 L = 0.126 mol/L
The original concentration of Na+ in serum is approximately 0.126 M.
Learn more about Original Na+ Concentration Calculation here:https://brainly.com/question/39426071
#SPJ3
Show the determination of the charge of the ion formed by the Mg12 atom.
Explanation:
It is known that the atomic number of magnesium is 12 and its electronic distribution is 2, 8, 2. And, in order to attain stability a magnesium atom will tend to lose its valence electrons.
That is, being a metal magnesium atom will lose its 2 valence electrons and hence it forms a [tex]Mg^{2+}[/tex] ion.
Equation for this type of loss is as follows.
[tex]Mg \rightarrow Mg^{2+} + 2e^{-}[/tex]
Therefore, we can conclude that the charge of the ion formed by the [tex]_{12}Mg[/tex] atom is +2.
Challenge question: This question is worth 6 points. As you saw in problem 9 we can have species bound to a central metal ion. These species are called ligands. In the past we have assumed all the d orbitals in some species are degenerate; however, they often are not. Sometimes the ligands bound to a central metal cation can split the d orbitals. That is, some of the d orbitals will be at a lower energy state than others. Ligands that have the ability to cause this splitting are called strong field ligands, CN- is an example of these. If this splitting in the d orbitals is great enough electrons will fill low lying orbitals, pairing with other electrons in a given orbital, before filling higher energy orbitals. In question 7 we had Fe2+, furthermore we found that there were a certain number (non-zero) of unpaired electrons. Consider now Fe(CN)64-: here we also have Fe2+, but in this case all the electrons are paired, yielding a diamagnetic species. How can you explain this?
A. There are 3 low lying d orbitals, which will be filled with 6 electrons before filling the 2, assumed to be degenerate, higher energy orbitals.
B. There are 4 low lying d orbitals, which will be filled with 8 electrons before filling the 1 higher energy orbital.
C. There is 1 low lying d orbital, which will be filled with two electrons before filling the 4, assumed to be degenerate, higher energy orbitals.
D. All the d orbitals are degenerate.
E. There are 2 low lying d orbitals, which will be filled with 4 electrons before filling the 3, assumed to be degenerate, higher energy orbitals.
Answer:
A
Explanation:
Iron has the ground state electronic configuration [Ar]3d64s2
Fe2+ has the electronic configuration [Ar]3d6.
In an octahedral crystal field, there are two sets of degenerate orbitals; the lower lying three t2g orbitals, and the higher level two degenerate eg orbitals. Strong field ligands cause high octahedral crystal field splitting, there by separating the two sets of degenerate orbitals by a tremendous amount of energy. This energy is much greater than the pairing energy required to pair the six electrons in three degenerate orbitals. Since CN- is a strong field ligand, it leads to pairing of six electrons in three degenerate orbitals
The Fe(CN)64- ion is diamagnetic due to the significant energy difference caused by strong field ligands like CN-, resulting in pairing of electrons in the 3 low energy d orbitals before filling the higher energy ones.
Explanation:The answer is A. There are 3 low lying d orbitals, which will be filled with 6 electrons before filling the 2, assumed to be degenerate, higher energy orbitals. When a metal ion is coordinated to ligands, such as in Fe(CN)64-, the degeneracy of the 3d orbitals is broken (they have different energies), due to the electrostatic interactions between the ligands and the orbitals. In the case of strong-field ligands like CN-, the energy difference is significant enough to cause pairing of electrons in the 3 low energy d orbitals before the 2 high energy orbitals are populated, resulting in a diamagnetic species.
Learn more about Crystal Field Theory here:https://brainly.com/question/35613395
#SPJ3
A 0.588 g sample of a nonvolatile, yellow crystalline solid dissolves in 11.5 g of benzene, producing a solution that freezes at 5.02 oC. Find the molar mass of the yellow solid. The following may be useful: The freezing point of benzene is 5.51 oC and the freezing point depression constant, kf, is 4.90 oC/m.
Answer:
The molar mass of the solid is 511.3 g/mol
Explanation:
Step 1: Data given
Mass of the sample = 0.588 grams
Mass of benzene = 11.5 grams
The solution freezes at 5.02 °C
The freezing point of benzene is 5.51 °C
The freezing point depression constant, kf = 4.90 °C/m
Step 2: Determine the temperature change
Δt = 5.51 - 5.02 = 0.49°C
Step 3: Determine number of moles
Δt = i*Kf*m
⇒ with i = the number of dissolved particles the solute produces = 1
⇒ with Kf = the molal freezing point depression constant Kf = 4.90 °C*Kg/mol
⇒ with m = the molality of the solute
0.49 °C = (1) (4.90 °C kg/mol) (x / 0.01150 kg)
x = 0.00115 mol
Step 4: Calculate molar mass
0.588 grams / 0.00115 mol = 511.3 g/mol
The molar mass of the solid is 511.3 g/mol
A sample weighing 3.110 g is a mixture of Fe 2 O 3 (molar mass = 159.69 g/mol) and Al 2 O 3 (molar mass = 101.96 g/mol). When heat and a stream of H 2 gas is applied to the sample, the Fe 2 O 3 reacts to form metallic Fe and H 2 O ( g ) . The Al 2 O 3 does not react. If the sample residue (the solid species remaining after the reaction) weighs 2.387 g, what is the mass fraction of Fe 2 O 3 in the original sample?
Answer:
The mass fraction of ferric oxide in the original sample :[tex]\frac{723}{3110}[/tex]
Explanation:
Mass of the mixture = 3.110 g
Mass of [tex]Fe_2O_3=x[/tex]
Mass of [tex]Al_2O_3=y[/tex]
After heating the mixture it allowed to react with hydrogen gas in which all the ferric oxide reacted to form metallic iron and water vapors where as aluminum oxide did not react.
[tex]Fe_2O_3(s)+3H_2(g)\rightarrow 2Fe(s)+3H_2O(g)[/tex]
Mass of mixture left after all the ferric oxide has reacted = 2.387 g
Mass of mixture left after all the ferric oxide has reacted = y
[tex]x=3.110 g- y=3.110 g - 2.387 g = 0.723 g[/tex]
The mass fraction of ferric oxide in the original sample :
[tex]\frac{0.723 g}{3.110 g}=\frac{723}{3110}[/tex]
A mixture of gaseous reactants is put into a cylinder, where a chemical reaction turns them into gaseous products. The cylinder has a piston that moves in or out, as necessary, to keep a constant pressure on the mixture of . The cylinder is also submerged in a large insulated water bath. (See sketch at right.) From previous experiments, this chemical reaction is known to release of energy. The temperature of the water bath is monitored, and it is determined from this data that of heat flows out of the system during the reaction.
a)Exothermic
b) it goes up
c) The piston must move out
d)The energy is released by the system
e)ΔE = -616 kJ
Explanation:
sign convention for heat flow:
if the heat flows into the system it is marked with positive sign
when the heat flows out the system it is marked with negative sign
sign convention for work
if work is done on the system it is marked positive
if work is done by the system it is marked negative
sign convention for internal energy
if energy absorbed by system mark positive
if energy released by system mark negative
a)
the heat flow flowing out of the system (q= -300 kJ)
thus the reaction is Exothermic
b)
In exothermic reaction, heat flows from the system to surroundings.
surrounding here is water bath.
As the system is exothermic, hence the temperature of water bath goes up
c)
It is given that 316 kJ of work is done by the system, applying expansion.
To maintain constant pressure of 1 atm the decreased pressure can be compensated with an increase on volume . To increase volume the piston must move out
d)
According to 1st law of thermodynamics,
ΔE =q +w ⇒1
here,
ΔE = q +w
ΔE = -300 kJ -316 kJ
ΔE = -616 kJ ⇒2
the negative sign denotes the energy is released by the system
e)
from ΔE = -616 kJ the amount of energy released by the reaction is ΔE = -616kJ
The Michaelis-Menten equation is an expression of the relationship between the initial velocity,V0, of an enzymatic reaction and substrate concentration, [S]. There are three conditions that are useful for simplifying the Michaelis-Menten equation to an expression from which the effect of [S] on the rate can be more readily determined. Match the condition (e.g. [S] = Km) with the statement(s) that describe it:
1. Doubling [S] will almost double the rate.
2. Half of the active sites are occupied by substrate.
3. About 90% of the active sites are occupied by substrate.
4. Doubling [S] will have little effect on the rate.
5. Less than 10% of the active sites are occupied by substrate.
6. This condition will result in the highest rate.
There are three conditions for simplifying the Michaelis-Menten equation: when [S] is significantly less than Km, when [S] equals Km, and when [S] is much larger than Km. These are associated with less than 10% and half of the active sites being occupied by the substrate, and with doubling [S] either almost doubling the rate or having little effect.
Explanation:The Michaelis-Menten equation expresses the relationship between the initial enzymatic reaction velocity, V₀, and the substrate concentration, [S]. It allows for a simplification of the relationship between [S] and rate, given certain conditions:
[S]<[S] = Km: This relates to statement 2: half of the active sites are occupied by the substrate.[S]>>Km: This condition, where [S] greatly exceeds Km, matches with statement 3: approximately 90% of the active sites are occupied by the substrate. Doubling [S] will have little impact on the rate (statement 4), and the highest rate will be reached (statement 6).Understanding these conditions can significantly simplify the usage of the Michaelis-Menten equation in exploring enzyme kinetics.
Learn more about Michaelis-Menten equation here:https://brainly.com/question/30404535
#SPJ3
A sample of methane at a pressure of 1.00 atm and a temperature of 93.1 K is heated at constant pressure to a temperature of 158 K. Which of the following are true? Choose all that apply
a. The liquid initially present will solidify.
b. The final state of the substance is a gas.
c. The sample is initially a solid.
d. The sample is initially a liquid. One or more phase changes will occur.
Answer:
b. The final state of the substance is a gas.
d. The sample is initially a liquid. One or more phase changes will occur.
Explanation:
Methane has the following properties:
Normal melting point: 90.7 KNormal boiling point: 111.65 K*"Normal" refers to normal pressure (1 atm).
According to this, we can affirm:
Below 90.7 K, methane is solid.Between 90.7 K and 111.65 K, methane is liquid.Above 111.65 K, methane is gas.A sample of methane at a pressure of 1.00 atm and a temperature of 93.1 K is heated at constant pressure to a temperature of 158 K. Which of the following are true? Choose all that apply.
a. The liquid initially present will solidify. FALSE. The liquid will vaporize.
b. The final state of the substance is a gas. TRUE.
c. The sample is initially a solid. FALSE. The sample is initially a liquid.
d. The sample is initially a liquid. One or more phase changes will occur. TRUE.
The substance would start as a gas, then transition to a solid without becoming a liquid due to temperature conditions.
The substance would begin as a gas and as the pressure increases, it would compress and eventually solidify without liquefying as the temperature is below the triple point temperature.
Describe the phase changes from -80°C to 500°C at 2 atm.
The sample is initially a gas, condenses to a solid as the pressure increases, and then melts when the pressure is increased further to give a liquid.
In chemistry, some reactions are linked to other reactions. For example, in the decomposition of potassium chlorate, oxygen and potassium chloride are produced. Then, the oxygen can react with magnesium and produce magnesium oxide. Using the reactions below, if you start with exactly 6 moles of potassium chlorate, how much magnesium oxide can you produce? 2 KClO3 → 3 O2 + 2 KCl 2 Mg + O2 → 2 MgO
A. 18 moles
B. 5 moles
C. 6 moles
D. 2 moles
Answer:
C
Explanation:
If 2 moles of potassium chlorate produced 2 moles of MgO, then 2*6/2 moles of MgO are produced when 6 moles of potassium perchlorate is used.
Identify and label the Brønsted-Lowry acid, its conjugate base, the Brønsted-Lowry base, and its conjugate acid in each of the following equations:
(a) HNO3+H2O⟶H3O++NO3−
(b) CN− +H2O ⟶ HCN+OH−
(c) H2SO4+Cl− ⟶HCl+HSO4−
(d) HSO4−+OH− ⟶SO42−+H2O
(e) O2− + H2 O ⟶ 2OH−
Explanation:
As per Brønsted-Lowry concept of acids and bases, chemical species which donate proton are called Brønsted-Lowry acids.
The chemical species which accept proton are called Brønsted-Lowry base.
(a) [tex]HNO_3 + H_2O \rightarrow H_3O^+ + NO_3^-[/tex]
[tex]HNO_3[/tex] is Bronsted lowry acid and [tex]NO_3^-[/tex] is its conjugate base.
[tex]H_2O[/tex] is Bronsted lowry base and [tex]H_3O^+[/tex] is its conjugate acid.
(b)
[tex]CN^- + H_2O \rightarrow HCN + OH^-[/tex]
[tex]CN^-[/tex] is Bronsted lowry base and HCN is its conjugate acid.
[tex]H_2O[/tex] is Bronsted lowry acid and [tex]OH^-[/tex] is its conjugate base.
(c)
[tex]H_2SO_4 + Cl^- \rightarrow HCl + HSO_4^-[/tex]
[tex]H_2SO_4[/tex] is Bronsted lowry acid and [tex]HSO_4^-[/tex] is its conjugate base.
Cl^- is Bronsted lowry base and HCl is its conjugate acid.
(d)
[tex]HSO_4^-+OH^- \rightarrow SO_4^{2-}+H_2O[/tex]
[tex]HSO_4^-[/tex] is Bronsted lowry acid and [tex]SO_4^{2-}[/tex] is its conjugate base.
OH^- is Bronsted lowry base and [tex]H_2O[/tex] is its conjugate acid.
(e)
[tex]O_{2-}+H_2O \rightarrow 2OH^-[/tex]
[tex]O_{2-}[/tex] is Bronsted lowry base and OH- is its conjugate acid.
[tex]H_2O[/tex] is Bronsted lowry acid and OH- is its conjugate base.
The identification and labelling of the Brønsted-Lowry acid and base, and their respective conjugate are done below.
What is Brønsted-Lowry acid and base?Brønsted-Lowry acids are chemical species that donate proton (H+) while the chemical species which accept proton (H+) are called Brønsted-Lowry base
Based on this question, the conjugate acid and base of the equations given are as follows:
For equation a:
HNO3 is the Bronsted lowry acid and NO3- is its conjugate base.H2O is Bronsted lowry base while H3O+ is its conjugate acid.For equation b:
Cyanide ion is the Bronsted lowry base while hydrogen cyanide is its conjugate acid. H2O is the Bronsted lowry acid while OH- is its conjugate base.For equation c:
H2SO4 is the Bronsted lowry acid while HSO4- is its conjugate base.Cl- is the Bronsted lowry base and HCl is its conjugate acid.For equation d:
HSO4- is the Bronsted lowry acid while SO4²- its conjugate base.OH- is the Bronsted lowry base and H2O is its conjugate acidFor equation e:
O²- is the Bronsted lowry base and OH- is its conjugate acid.H2O is the Bronsted lowry acid and OH- is its conjugate baseLearn more about Brønsted-Lowry base and acid at: https://brainly.com/question/21736327
Azomethane decomposes into nitrogen and ethane at elevated temperature: H3C–N=N–CH3 → N2 + C2H6 A chemist studying this reaction at 300°C begins an experiment with an azomethane concentration of 4.52 mM and obtains the following data: Time(s) 100 150 200 250 300 [Azomethane] (mM) 3.50 3.08 2.71 2.39 2.10 Calculate the rate constant. Give an answer with concentration units of molarity and time units of seconds.
Answer:
k = 0,0026 s⁻¹
Explanation:
To calculate the rate constant it is necessary to find out the order of reaction. The R² nearest 1 will be the order of reaction.
For zeroth order the integrated rate law is:
[A] = [A]₀ -kt
The graph of [A] vs t gives a correlation coefficient R² of 0,9944.
The first order is:
ln [A] = ln [A]₀ -kt
The graph of ln [A] vs t gives a R² of 1
The second order is:
1/[A] = 1/[A]₀ -kt
The graph of 1/[A] vs t gives a R² of 0,9942
As R² = 1 for first order, the descomposition of azomethane follows this kinetics order. The lineal correlation is:
y = b - mx
y = 1,5077 - 0,0026x
ln [A] = ln [A]₀ -kt
That means:
-k = - 0,0026 s⁻¹
k = 0,0026 s⁻¹
I hope it helps!
A mixture contains 25 g of cyclohexane (C6H12) and 44 g of 2-methylpentane (C6H14). The mixture of liquids is at 35 oC . At this temperature, the vapor pressure of pure cyclohexane is 150 torr, and that of pure 2-methylpentane is 313 torr. Assume this is an ideal solution. What is the mole fraction of cyclohexane in the liquid phase?
Answer:
The mol fraction of cyclohexane in the liquid phase is 0.368
Explanation:
Step 1: Data given
Mass of cyclohexane = 25.0 grams
Mass of 2-methylpentane = 44.0 grams
Temperature = 35.0 °C
The pressure of cyclohexane = 150 torr
The pressure of 2-methylpentane = 313 torr
The pressure we only need for the mole fraction in gas phase.
Step 2: Calculate moles of cyclohexane
Moles cyclohexane = mass cyclohexane / molar mass
Moles cyclohexane = 25.0 g / 84 g/mol = 0.298 mol of cyclohexane
Step 3: Calculate moles of 2-methylpentane
Moles = 44.0 grams / 86 g/mol = 0.512 mol of 2-methylpentane
Step 4: Calculate mole fraction of cyclohexane in the liquid phase
Mole fraction of C6H12:
0.298 / (0.298 + 0.512) = 0.368
The mol fraction of cyclohexane in the liquid phase is 0.368
The mole fraction of cyclohexane in the liquid phase is 36.8%.
Explanation:To find the mole fraction of cyclohexane in the liquid phase, we need to calculate the total moles of cyclohexane and 2-methylpentane in the mixture. First, we calculate the moles of each component using their molar masses:
moles of cyclohexane = 25 g / 84.18 g/mol = 0.297 mol
moles of 2-methylpentane = 44 g / 86.18 g/mol = 0.509 mol
Next, we calculate the mole fraction of cyclohexane:
mole fraction of cyclohexane = moles of cyclohexane / (moles of cyclohexane + moles of 2-methylpentane)
mole fraction of cyclohexane = 0.297 mol / (0.297 mol + 0.509 mol) = 0.368 or 36.8%
The equilibrium constant is given for one of the reactions below.
Determine the value of the missing equilibrium constant.
2 HD(g) ⇌ H2(g) + D2(g) Kc = 0.28
2 H2(g) + 2 D2(g) ⇌ 4 HD(g)
To find the missing equilibrium constant, we can use stoichiometry and the first given equilibrium constant. The missing equilibrium constant for the second reaction is the square of the given Kc value.
Explanation:To determine the missing equilibrium constant, you can use the concept of equilibrium constant expressions.
In the first reaction, 2 HD(g) ⇌ H2(g) + D2(g), the equilibrium constant is given as Kc = 0.28.
To find the value of the missing equilibrium constant for the second reaction, 2 H2(g) + 2 D2(g) ⇌ 4 HD(g), we can use the stoichiometry.
Since the equilibrium constant is a ratio of product concentrations to reactant concentrations, and the stoichiometric coefficients for the second reaction are all multiplied by 2 compared to the first reaction, the missing equilibrium constant would be the square of the given Kc value.
Therefore, the missing equilibrium constant is 0.28 squared, which is approximately 0.0784.
The equilibrium constant for the reaction 2 H₂(g) + 2 D₂(g) ⇌ 4 HD(g) is D) 13
To determine the equilibrium constant for the reaction 2 H₂(g) + 2 D₂(g) ⇌ 4 HD(g) given the equilibrium constant for the reverse reaction, 2 HD(g) ⇌ H₂(g) + D₂(g), which is Kc = 0.28, we can use the concept that the equilibrium constant for the reverse reaction is the reciprocal of the equilibrium constant for the forward reaction.
The given reaction is:
2 HD(g) ⇌ H₂(g) + D₂(g), Kc = 0.28
The reverse reaction is:
H₂(g) + D₂(g) ⇌ 2 HD(g), K'c = 1 / 0.28
K'c = 3.57
The target reaction is twice the reverse reaction:
2 H₂(g) + 2 H₂(g) ⇌ 4 HD(g)
When the reaction coefficients are doubled, the equilibrium constant is squared:
Kc = K'c²
Kc = 3.57² = 12.75
Therefore, the equilibrium constant for the reaction 2 H₂(g) + 2 D₂(g) ⇌ 4 HD(g) is 12.798
Rounding of to two significant figures, the Equilibrium constant is D) 13
Complete question is - The equilibrium constant is given for one of the reactions below. Determine the value of the missing equilibrium constant.
2 HD (g) = H2 (g) + D2 (g) Kc = 0.28
2 H2 (g) + 2 D2 (g) = 4 HD (g) Kc = ?
A) 7.8 x 10⁻²
B) 3.6
C) 0.53
D) 13
E) 1.9
he equilibrium constant is equal to 5.00 at 1300 K for the reaction:2 SO2(g) + O2(g) ↔ 2 SO3(g).If initial concentrations are [SO2] = 6.00 M, [O2] = 0.45 M, and [SO3] = 9.00 M, the system isnot at equilibrium and will shift to the right to achieve an equilibrium state.not at equilibrium and will shift to the left to achieve an equilibrium state.at equilibrium.not at equilibrium and will remain in an unequilibrated state.
Answer:
The system is at equilibrium
Explanation:
Let's consider the following reversible reaction.
2 SO₂(g) + O₂(g) ⇄ 2 SO₃(g)
To determine whether a reaction is at equilibrium or not, we have to calculate the reaction quotient (Q).
[tex]Q=\frac{[SO_{3}]^{2}}{[SO_{2}]^{2}.[O_{2}]} =\frac{(9.00)^{2} }{(6.00)^{2}\times 0.45} =5.0[/tex]
Since Q = K (equilibrium constant), regardless of the significant figures, the system is at equilibrium.
The correct answer is at equilibrium.
The initial concentrations given correspond to the equilibrium concentrations for the reaction at 1300 K, and no shift in the reaction direction is necessary to achieve equilibrium because [tex]\( Q = K \).[/tex]
The equilibrium position of the reaction under the given conditions, we need to compare the initial concentrations with the equilibrium concentrations and the equilibrium constant [tex]\( K \).[/tex]
Given.
- Equilibrium constant K = 5.00
- Initial concentrations.
- [tex]\([SO_2]_{\text{initial}} = 6.00 \)[/tex] M.
- [tex]\([O_2]_{\text{initial}} = 0.45 \)[/tex] M.
- [tex]\([SO_3]_{\text{initial}} = 9.00 \)[/tex] M.
The reaction is. [tex]\( 2 SO_2(g) + O_2(g) \leftrightarrow 2 SO_3(g) \)[/tex]
1.Calculate Reaction Quotient Q
[tex]\[ Q = \frac{[\text{SO}_3]^2}{[\text{SO}_2]^2 [\text{O}_2]} \][/tex]
Substitute the initial concentrations into the expression for [tex]\( Q \).[/tex]
[tex]\[ Q = \frac{(9.00)^2}{(6.00)^2 \times 0.45} \][/tex]
[tex]\[ Q = \frac{81.00}{16.20} \][/tex]
[tex]\[ Q \approx 5.00 \][/tex]
2. Compare Q with K.
- Q = 5.00
- K = 5.00
Since Q the reaction quotient is equal to K the equilibrium constant the system is already at equilibrium.
In the presence of excess oxygen, methane gas burns in a constant-pressure system to yield carbon dioxide and water:
CH4 (g) + 2O2 (g) → CO2 (g) + 2H2O DH = -890.0 kJ
Calculate the value of q (kJ) in this exothermic reaction when 1.70 g of methane is combusted at constant pressure.
Answer:
94.56KJ
Explanation:
1.7 grams of CH4 contains 1.7/16 moles of CH4.
If 1 mole of CH4 give 890KJ
1.7/16 moles of CH4 gives 1.7/16*890 = 94.56KJ
Most metals are very reactive, as are the elements in the halogen group. Aluminum, for instance, For example, reacts with elemental chlorine to form aluminum chloride. If you have a 13.5 g sample of Al, which choice below is true?
A. you will need 23.6 g Cl2 for complete reaction and will produce 66.7 g of AlCl3.
B. you will need 53.2 g Cl2 for complete reaction and will produce 66.7 g of AlCl3.
C. you will need 11.8 g Cl2 for complete reaction and will produce 49.0 g of AlCl3.
D. you will need 26.6 g Cl2 for complete reaction and will produce 49.0 g of AlCl3. Reset Selection
Answer: B. you will need 53.2 g Cl2 for complete reaction and will produce 66.7 g of AlCl3.
Explanation:
According to avogadro's law, 1 mole of every substance occupies 22.4 L at STP and contains avogadro's number [tex]6.023\times 10^{23}[/tex] of particles.
To calculate the moles, we use the equation:
[tex]\text{Number of moles of aluminium}=\frac{\text{Given mass}}{\text {Molar mass}}=\frac{13.5g}{27g/mol}=0.5moles[/tex]
The balanced reaction is:
[tex]2Al+3Cl_2(g)\rightarrow 2AlCl_3[/tex]
2 moles of aluminium react with= 3 moles of chlorine
Thus 0.5 moles of aluminium react with=[tex]\frac{3}{2}\times 0.5=0.75[/tex] moles of chlorine
Mass of chlorine=[tex]moles\times {\text{Molar Mass}}=0.75\times 71=53.2g[/tex]
2 moles of aluminium produce = 2 moles of aluminium chloride
Thus 0.5 moles of aluminium react with=[tex]\frac{2}{2}\times 0.5=0.5[/tex] moles of aluminium chloride
Mass of aluminium chloride=[tex]moles\times {\text{Molar Mass}}=0.5\times 133.34=66.7g[/tex]
Thus 53.2 g of chlorine is used and 66.7 g of aluminium chloride is produced.
Lithium aluminum hydride reduces carboxylic acids to primary alcohols via what intermediate?A) a ketone. B) a methyl ester. C) an aldehyde. D) a secondary alcohol. E) an acid chloride.
Final answer:
Lithium aluminum hydride reduces carboxylic acids to primary alcohols via an aldehyde intermediate, although the aldehyde is not isolated and is reduced further to a primary alcohol in one step. So the correct option is C.
Explanation:
Lithium aluminum hydride reduces carboxylic acids to primary alcohols by first forming an aldehyde as the intermediate. The reduction process does not stop at the aldehyde stage but proceeds to reduce the aldehyde further to a primary alcohol. When a carboxylic acid is reduced, the process typically bypasses the isolation of the intermediate aldehyde due to the strong reducing power of lithium aluminum hydride (LiAlH4), which is capable of fully reducing the carboxylic acid to the alcohol in one step.
The drug molecules bind the protein in a 1:1 ratio to form a drug-protein complex. The protein concentration in aqueous solution at 25 ∘C is 1.60×10−6 M . Drug A is introduced into the protein solution at an initial concentration of 2.00×10−6M. Drug B is introduced into a separate, identical protein solution at an initial concentration of 2.00×10−6M. At equilibrium, the drug A-protein solution has an A-protein complex concentration of 1.00×10−6M, and the drug B solution has a B-protein complex concentration of 1.40×10−6M.a. Calculate the Kc value for the A-protein binding reaction.b. Calculate the Kc value for the B-protein binding reaction.c. Assuming that the drug that binds more strongly will be more effective, which drug is the better choice for further research?
Answer:
a. kc = 1,67x10⁶
b. kc = 1,17x10⁷
c. Drug B is the better choice.
Explanation:
The bind of drug-protein is described as:
Protein + Drug ⇄ Drug-protein
Where kc is:
kc = [Drug-protein] / [Protein] [Drug] (1)
a. For A, the equilibrium concentration of each specie is:
[Protein]: 1,60x10⁻⁶M - x
[Drug]: 2,00x10⁻⁶M - x
[Drug-protein]: x = 1,00x10⁻⁶M
-Where x is reaction coordinate-
Thus:
[Protein]: 1,60x10⁻⁶M - 1,00x10⁻⁶M = 0,60x10⁻⁶M
[Drug]: 2,00x10⁻⁶M - 1,00x10⁻⁶M = 1,00x10⁻⁶M
Replacing in (1):
kc = [1,00x10⁻⁶] / [1,00x10⁻⁶] [0,60x10⁻⁶]
kc = 1,67x10⁶
b. For B:
[Protein]: 1,60x10⁻⁶M - x
[Drug]: 2,00x10⁻⁶M - x
[Drug-protein]: x = 1,40x10⁻⁶M
-Where x is reaction coordinate-
Thus:
[Protein]: 1,60x10⁻⁶M - 1,40x10⁻⁶M = 0,20x10⁻⁶M
[Drug]: 2,00x10⁻⁶M - 1,40x10⁻⁶M = 0,60x10⁻⁶M
Replacing in (1):
kc = [1,40x10⁻⁶] / [0,20x10⁻⁶] [0,60x10⁻⁶]
kc = 1,17x10⁷
c. The drug with the bigger kc will be the more effective because will be the drug that binds more strongly with the protein. Thus, drug B is the better choice.
I hope it helps!
The Kc values for the A-protein and B-protein binding reactions are 3.125 and 4.375, respectively. Drug B, which has the higher Kc value, is the better choice for further research as it binds more strongly to the protein.
Explanation:a. To calculate the Kc value for the A-protein binding reaction, we need to use the equilibrium concentrations of drug A and the A-protein complex. The Kc value is given by [A-protein complex] / ([A] * [protein]). Plugging in the values, we get Kc = (1.00×10^6) / ((2.00×10^6) * (1.60×10^−6)) = 3.125.
b. Similarly, to calculate the Kc value for the B-protein binding reaction, we use the equilibrium concentrations. Kc = (1.40×10^6) / ((2.00×10^6) * (1.60×10^−6)) = 4.375.
c. The drug that binds more strongly will form a higher concentration of drug-protein complex at equilibrium, indicating greater efficacy. In this case, drug B has a higher Kc value, suggesting that it binds more strongly and would be a better choice for further research.
Learn more about Drug-protein binding here:https://brainly.com/question/31595504
#SPJ6
A voltaic cell utilizes the following reaction: 4Fe2+(aq)+O2(g)+4H+(aq)→4Fe3+(aq)+2H2O(l).
The EMF under standard contions is .46 V.
What is the emf of this cell when [Fe2+]= 2.0M , [Fe3+]= 1.9
Answer:
The Emf of the given cell at [Fe2+] = 2.0 M and [Fe3+] = 1.9 M is 0.48 V
Explanation:
The half cell reaction can be written as :
Anode-Half (oxidation) :
[tex]Fe^{2+}\rightarrow Fe^{3+} + 1e^{-}[/tex] ......E = 0.77 V
(multiply this equation by 4 to balance the electrons)
Cathode-half (reduction)
[tex]4H^{+} +O_{2} + 4e^{-} \rightarrow 2H_{2}O[/tex]....E= 1.23 V
[tex]E^{0}_{cell} = E_{cathode} - E_{anode}[/tex]
[tex]E^{0}_{cell} = 1.23 - 0.77[/tex]
[tex]E^{0}_{cell} = 0.46 V[/tex]
According to Nernst Equation
[tex]E_{cell} = E^{0} - \frac{RT}{nF}lnQ[/tex]
[tex]E_{cell} = E^{0} - \frac{0.059}{n}logQ[/tex]
n = number of electron transferred in the cell reaction = 4
The balanced equation is :
[tex]4Fe^{2+} + 4H^{+} +O_{2} \rightarrow 4Fe^{3+} + 2H_{2}O[/tex]
[tex]E_{cell} = 0.46 - \frac{0.059}{4}logQ[/tex]
[tex]log Q = \frac{[Fe^{3+}]^{4}}{[Fe^{2+}]^{4}}[/tex]
[tex]log Q = \left ( \frac{[Fe^{3+}]}{[Fe^{2+}]} \right )^{4}[/tex]
[tex]log Q = \left ( \frac{1.9}{2.0} \right )^{4}[/tex]
Insert the value of log Q in Nernst Equation:
[tex]E_{cell} = 0.46 - \frac{0.059}{4} log\left ( \frac{1.9}{2.0} \right )^{4}[/tex]
(using :[tex]log^{a}b = a\log b[/tex]
)
[tex]E_{cell} = 0.46 - log\frac{1.9}{2.0}[/tex]
[tex]E_{cell} = 0.46 - log(0.95)[/tex]
[tex]E_{cell} = 0.46 -(-0.0227)[/tex]
[tex]E_{cell} = 0.482 V[/tex]
The cell EMF is obtained from Nernst equation as 0.451 V.
The reaction equation is given by;
4Fe2+ (aq) + O2(g) + 4H+ (aq)-------->4Fe3+(aq)+2H2O(l)
We have the following information;
EMF under standard conditions = 0.46 V
[Fe2+]= 2.0M
[Fe3+]= 1.9 M
From Nernst equation;
Ecell = E°cell - 0.0592/n logQ
Where;
E°cell = 0.46 V
n = 4
Q = [Fe3+]^4/ [Fe2+]^4
Q = [1.9]^4/[2.0]^4
Q = 0.8
Substituting values;
Ecell = 0.46 - 0.0592/4 log (0.8)
Ecell = 0.451 V
Learn more:https://brainly.com/question/10643807
Radon is a radioactive noble gas that can sometimes be found in unventilated basements. A sample of 1.35×10−4mol of radon gas is held in a container with a volume of 3.03mL. A quantity of radon gas is added to the container, which is then found to have a volume of 7.79mL at the same temperature and pressure. How many moles of radon were added to the container?
Answer:
2.12*10^-4 moles
Explanation:
If 3.03ml contains 1.35*10^-4mol then 7.79 will contain 7.79ml*1.35*10^-4/3.03= 3.47*10^-4 moles
Amount added= (3.47-1.35)*10^-4=2.12*10^-4moles
Answer: 2.12 X 10^-4
Explanation:
First, find the final number of moles of radon in the container after the addition by rearranging Avogadro's law to solve for n2.
n2= V2 × n1 / V1
Substitute the known values ofn1, V1, and V2.
n2 = 7.79 mL × 1.35 × 10^−4 mol / 3.03 mL = 3.47 × 10^−4 mol
Find the difference between the final number of moles (n2) and the initial number of moles (n1).
n2−n1 = 3.47 × 10^-4 mol −1 .35 × 10^−4 mol= 2.12 × 10^−4mol
Organic matter with a _______ ratio results in a low net release of nutrients during decomposition. This is because microbial growth is more limited by _______ than it is by _______. low C:N; energy; N supply high C:N; N supply; energy high C:H2O; water supply; energy low C:H2O; energy; water supply low N:H2O; N supply; water supply
Answer:
high C:N; N supply; energy
Explanation:
Nitrogen supply is required for microbial growth to synthesize nutrients such as amino acids and proteins. For a high C:N ratio, the amount of nitrogen supply is considerably small compared with the amount of carbon. As a result, a low amount of nutrients is released during decomposition.
In the given question, the organic matter with a __high C:N___ ratio results in a low net release of nutrients during decomposition. This is because microbial growth is more limited by __N supply____ than it is by __energy_____.
Write the values for the four quantum numbers for a 4f6 electron.2.Write the values for the four quantum numbers for a 3s1 electron.3.Write the values for the four quantum numbers for the last electron to fill 28Ni.4.Write the values for the four quantum numbers for the outermost electron in 22Ti.
The electron configuration shows the arrangement of electrons in atoms.
The electron configuration gives a description of the location of the electron in an atom.
Note that;
n = Principal quantum number
l = orbital quantum number
m = magnetic quantum number
s = spin quantum number
For the 4f electron;n = 4, l = 3, m = 3, -2, -1, 0, 1, 2, 3, s= ±1/2
For the 3s electron;n = 3, l = 0, m = 0, s = ±1/2
For the last electron in Ni of electron configuration; [Ar] 3d⁸ 4s²n = 4, l = 0, m = 0, s = ±1/2
For the outermost electron in Ti of electron configuration; [Ar] 3d² 4s²n = 4, l = 0, m = 0, s = ±1/2
Learn more: https://brainly.com/question/11155928
Final answer:
The quantum numbers for specific electrons in the 4f6, 3s1, 28Ni, and 22Ti configurations have been provided according to their respective principal, azimuthal, magnetic, and spin quantum numbers.
Explanation:
The four quantum numbers are principal (n), azimuthal (l), magnetic (ml), and spin (ms). Here are their specified values for the given electrons:
Final answer:
The quantum numbers for specific electrons in the 4f6, 3s1, 28Ni, and 22Ti configurations have been provided according to their respective principal, azimuthal, magnetic, and spin quantum numbers.
Explanation:
The four quantum numbers are principal (n), azimuthal (l), magnetic (ml), and spin (ms). Here are their specified values for the given electrons:
a) Combustion analysis of toluene, a common organic solvent, gives 5.86 mg of CO2 and 1.37 mg of H2O. If the compound contains only carbon and hydrogen, what is its empirical formula?
b) Menthol, the substance we can smell in mentholated cough drops, is composed of C, H, and O. A 0.1005-g sample of menthol is combusted, producing 0.2829 g of CO2 and 0.1159 g of H2O. What is the empirical formula for menthol? If menthol has a molar mass of 156 g>mol, what is its molecular formula?
Answer:
For a: The empirical formula for the given compound is [tex]CH[/tex]
For b: The empirical and molecular formula for the given organic compound are [tex]C_{10}H_{20}O[/tex]
Explanation:
For a:The chemical equation for the combustion of hydrocarbon follows:
[tex]C_xH_y+O_2\rightarrow CO_2+H_2O[/tex]
where, 'x', and 'y' are the subscripts of Carbon and hydrogen respectively.
We are given:
Conversion factor used: 1 g = 1000 mg
Mass of [tex]CO_2=5.86mg=5.86\times 10^{-3}g[/tex]
Mass of [tex]H_2O=1.37mg=1.37\times 10^{-3}g[/tex]
We know that:
Molar mass of carbon dioxide = 44 g/mol
Molar mass of water = 18 g/mol
For calculating the mass of carbon:
In 44g of carbon dioxide, 12 g of carbon is contained.
So, in [tex]5.86\times 10^{-3}g[/tex] of carbon dioxide, [tex]\frac{12}{44}\times 5.86\times 10^{-3}=1.60\times 10^{-3}g[/tex] of carbon will be contained.
For calculating the mass of hydrogen:
In 18g of water, 2 g of hydrogen is contained.
So, in [tex]1.37\times 10^{-3}g[/tex] of water, [tex]\frac{2}{18}\times 1.37\times 10^{-3}=0.152\times 10^{-3}g[/tex] of hydrogen will be contained.
To formulate the empirical formula, we need to follow some steps:
Step 1: Converting the given masses into moles.Moles of Carbon = [tex]\frac{\text{Given mass of Carbon}}{\text{Molar mass of Carbon}}=\frac{1.60\times 10^{-3}g}{12g/mole}=0.133\times 10^{-3}moles[/tex]
Moles of Hydrogen = [tex]\frac{\text{Given mass of Hydrogen}}{\text{Molar mass of Hydrogen}}=\frac{0.152\times 10^{-3}g}{1g/mole}=0.152\times 10^{-3}moles[/tex]
Step 2: Calculating the mole ratio of the given elements.For the mole ratio, we divide each value of the moles by the smallest number of moles calculated which is [tex]0.133\times 10^{-3}[/tex] moles.
For Carbon = [tex]\frac{0.133\times 10^{-3}}{0.133\times 10^{-3}}=1[/tex]
For Hydrogen = [tex]\frac{0.152\times 10^{-3}}{0.133\times 10^{-3}}=1.14\approx 1[/tex]
Step 3: Taking the mole ratio as their subscripts.The ratio of C : H = 1 : 1
Hence, the empirical formula for the given compound is [tex]CH[/tex]
For b:The chemical equation for the combustion of menthol follows:
[tex]C_xH_yO_z+O_2\rightarrow CO_2+H_2O[/tex]
where, 'x', 'y' and 'z' are the subscripts of Carbon, hydrogen and oxygen respectively.
We are given:
Mass of [tex]CO_2[/tex] = 0.2829 g
Mass of [tex]H_2O[/tex] = 0.1159 g
We know that:
Molar mass of carbon dioxide = 44 g/mol
Molar mass of water = 18 g/mol
For calculating the mass of carbon:
In 44g of carbon dioxide, 12 g of carbon is contained.
So, in 0.2829 g of carbon dioxide, [tex]\frac{12}{44}\times 0.2829=0.077g[/tex] of carbon will be contained.
For calculating the mass of hydrogen:
In 18g of water, 2 g of hydrogen is contained.
So, in 0.1159 g of water, [tex]\frac{2}{18}\times 0.1159=0.013g[/tex] of hydrogen will be contained.
Mass of oxygen in the compound = (0.1005) - (0.077 + 0.013) = 0.105 g
To formulate the empirical formula, we need to follow some steps:
Step 1: Converting the given masses into moles.Moles of Carbon = [tex]\frac{\text{Given mass of Carbon}}{\text{Molar mass of Carbon}}=\frac{0.077g}{12g/mole}=0.0064moles[/tex]
Moles of Hydrogen = [tex]\frac{\text{Given mass of Hydrogen}}{\text{Molar mass of Hydrogen}}=\frac{0.013g}{1g/mole}=0.013moles[/tex]
Moles of Oxygen = [tex]\frac{\text{Given mass of oxygen}}{\text{Molar mass of oxygen}}=\frac{0.0105g}{16g/mole}=0.00065moles[/tex]
Step 2: Calculating the mole ratio of the given elements.For the mole ratio, we divide each value of the moles by the smallest number of moles calculated which is 0.00065 moles.
For Carbon = [tex]\frac{0.0064}{0.00065}=9.84\approx 10[/tex]
For Hydrogen = [tex]\frac{0.013}{0.00065}=20[/tex]
For Oxygen = [tex]\frac{0.00065}{0.00065}=1[/tex]
Step 3: Taking the mole ratio as their subscripts.The ratio of C : H : O = 10 : 20 : 1
The empirical formula for the given compound is [tex]C_{10}H_{20}O[/tex]
For determining the molecular formula, we need to determine the valency which is multiplied by each element to get the molecular formula.
The equation used to calculate the valency is:
[tex]n=\frac{\text{Molecular mass}}{\text{Empirical mass}}[/tex]
We are given:
Mass of molecular formula = 156 g/mol
Mass of empirical formula = 156 g/mol
Putting values in above equation, we get:
[tex]n=\frac{156g/mol}{156g/mol}=1[/tex]
Multiplying this valency by the subscript of every element of empirical formula, we get:
[tex]C_{(1\times 10)}H_{(1\times 20)}O_{(1\times 1)}=C_{10}H_{20}O[/tex]
Hence, the empirical and molecular formula for the given organic compound are [tex]C_{10}H_{20}O[/tex]
Final answer:
The empirical formula of toluene, derived from combustion yielding 5.86 mg of CO2 and 1.37 mg of H2O, is C7H8. For menthol, from 0.1005 g combusted to give 0.2829 g of CO2 and 0.1159 g of H2O and a molar mass of 156 g/mol, its empirical and molecular formulas are both C10H20O.
Explanation:
Empirical and Molecular Formulas of Organic Compounds
Combustion analysis is commonly used to determine the empirical formulas of organic compounds. The process involves burning a sample of the compound to produce CO2 and H2O, which can then be analyzed to determine the amounts of carbon and hydrogen in the original compound.
The empirical formula of toluene, given that combustion yields 5.86 mg of CO2 and 1.37 mg of H2O with only carbon and hydrogen present, can be found by:
Converting the mass of CO2 to moles of carbon.
Converting the mass of H2O to moles of hydrogen.
Determining the simplest whole number ratio of carbon to hydrogen atoms to find the empirical formula.
Following these steps, we can determine that the empirical formula of toluene is C7H8.
For menthol, with a 0.1005-g sample yielding 0.2829 g of CO2 and 0.1159 g of H2O, and a known molar mass of 156 g/mol, we:
Convert the masses of CO2 and H2O to moles of carbon and hydrogen, respectively.
Assume the rest of the mass is due to oxygen and calculate its moles.
Determine the empirical formula.
Calculate the molecular formula using the empirical formula and the given molar mass.
By doing so, we find that menthol's empirical formula is C10H20O and its molecular formula is also C10H20O.
Refrigerant-134a enters the coils of the evaporator of a refrigeration system as a saturated liquid-vapor mixture at a pressure of 160 kPa. The refrigerant absorbs 180 kJ/kg of heat from the cooled space, which is maintained at -5°C, and leaves as a saturated vapor at the same pressure. Determine
(a) the entropy change of the refrigerant,
(b) the entropy change of the cooled space, and
(c) the total entropy change for this process.
Answer:
(a) 0.699 kJ/K
(b) -0.671 kJ/K
(c) 0.028 kJ/K
Explanation:
The Refrigerant-134a flows into the evaporator as a saturated liquid-vapor mixture and flows out as a saturated vapor at a saturation pressure of 160 kPa and temperature of -15.64°C (estimated from the Saturated Refrigerant-134a Temperature Table).
(a) The entropy change of the refrigerant (ΔS[tex]_{R-134a}[/tex]) = Q/T[tex]_{1}[/tex]
Q = 180 kJ
T[tex]_{1}[/tex] = -15.64 + 273.15 = 257.51 K
ΔS[tex]_{R-134a}[/tex] = Q/T[tex]_{1}[/tex] = 180/257.51 = 0.699 kJ/K
(b) The entropy change (ΔS[tex]_{c}[/tex]) of the cooled space (ΔS[tex]_{c}[/tex]) = -Q/T[tex]_{2}[/tex]
Q = -180 kJ
T[tex]_{2}[/tex] = -5 + 273.15 = 268.15 K
ΔS[tex]_{c}[/tex] = Q/T[tex]_{2}[/tex] = -180/268.15 = -0.671 kJ/K
(c) The total entropy change for this process (ΔS[tex]_{t}[/tex]) = ΔS[tex]_{R-134a}[/tex] + ΔS[tex]_{c}[/tex] = 0.699 - 0.671 = 0.028 kJ/K
What is Δn for the following equation in relating Kc to Kp?2 SO2(g) + O2(g) ↔ 2 SO3(g)23-2-11
Answer:
-1
Explanation:
The relation between Kp and Kc is given below:
[tex]K_p= K_c\times (RT)^{\Delta n}[/tex]
Where,
Kp is the pressure equilibrium constant
Kc is the molar equilibrium constant
R is gas constant
T is the temperature in Kelvins
Δn = (No. of moles of gaseous products)-(No. of moles of gaseous reactants)
For the first equilibrium reaction:
[tex]2SO_2_{(g)}+O_2_{(g)}\rightleftharpoons2SO_3_{(g)} [/tex]
Δn = (2)-(2+1) = -1
Thus, Kp is:
[tex]K_p= K_c\times (RT)^{-1}[/tex]
You are measuring the concentration of Fe 2 in a sample is determined by measuring the absorbance of its complex with ferroxine. The sample, measured in a 1.00 cm cuvette, has an absorbance of 0.333 . The reagent blank in the same cuvette has an absorbance of 0.014 . What would be the absorbance reading for each of these two solutions if measured in a 5.00 cm cuvette?
Answer:
Sample: 1.67
Blank: 0.070
Explanation:
The absorbance of a solution (A) is explained by the Beer-Lambert law.
A = ε . l . c
where,
ε is the absorptivity of the species
l is the optical path length
c is the molar concentration of the species
As we can see, the absorbance is directly proportional to the path length, that is, the length of the cuvette. If l is increased 5 times (1.00 cm to 5.00 cm), the absorbance will also be increased 5 times.
The absorbance of the sample will be 5 × 0.333 = 1.67
The absorbance of the blank will be 5 × 0.014 = 0.070
According to Beer's law, if the cuvette size increases fivefold from 1.00 cm to 5.00 cm, the absorbance will also increase fivefold. Therefore, the absorbance of the sample would become 1.665, and the reagent blank would become 0.070.
Explanation:The absorbance of a solution is related to the path length (in this case, cuvette size) according to Beer's law, which states that A = εlc, where A is absorbance, ε is molar absorptivity, l is path length, and c is concentration. Thus, absorbance is directly proportional to the path length.
If the path length increases from 1.00 cm to 5.00 cm, the absorbance also increases by the same factor. Therefore, the absorbance of the sample and the reagent blank in a 5.00 cm cuvette would be:
Sample: 0.333 * (5.00 cm / 1.00 cm) = 1.665Reagent blank: 0.014 * (5.00 cm / 1.00 cm) = 0.070Learn more about Absorbance measurement here:https://brainly.com/question/32564177
#SPJ11
Stan is a member of the Association for Consumer Research, but when he attends the conferences, he doesn't identify with the group. Even though his research is received favorably, he often feels detached and perceives himself as different from the other members. Stan can best be described as having a(n) _____ self-schema with respect to this group.idealizedseparatedactualizedconnectedambiguous
Answer:
Separated
Explanation:
Stan does not feel he identifies closely with the group. He feels the other members are close knit with each other but he is not part of the group.
For Stan, it would be an illusion to say he has a close relationship with the members of the group
This infers that Stan has a separated self-schema with respect to the group.