Remember to explain and show work.
26. How much heat will be absorbed if 45.0 g of C react with excess water?
27. How much heat is released when 9.22 grams of glucose C6H12O6 in your body reacts with according to the following equation?
Answers
Answer:
26. 42.3 kJ; 27. 143 kJ
Explanation:
26. Formation of water gas
We know that we will need the balanced equation with masses, molar masses, and enthalpies, so let’s gather all the information in one place.
A_r: 12.01
C + H₂O ⟶ CO + H₂; ΔH_r = +113 kJ
Mass/g: 4.50
(a) Calculate the moles of C
Moles of C = 4.50 × 1/12.01 = 0.375 mol C
(b) Calculate the energy absorbed
The conversion factor is 113 kJ/1 mol Al
Heat = 0.375 × 113/1 = 42.3 kJ
27. Oxidation of glucose
A_r: 180.16
C₆H₁₂O₆ + 6O₂ ⟶ 6CO₂ + 6H₂O; ΔH_r = -2803 kJ
Mass/g: 9.22
(a) Calculate the moles of C₆H₁₂O₆
Moles of C₆H₁₂O₆ = 9.22 × 1/180.16 = 0.051 07 mol C₆H₁₂O₆
(b) Calculate the energy absorbed
The conversion factor is (-2803 kJ/1 mol C₆H₁₂O₆)
Heat = 0.051 07 × (-2803)/1 = -143 kJ
The oxidation of glucose releases 143 kJ .
Related Questions
An aluminum oxide component must not fail when a tensile stress of 16.5 mpa is applied. determine the maximum allowable surface crack length if the surface energy of aluminum oxide is 0.90 j/m2. the modulus of elasticity of this material is 393 gpa.
Answers
90 per square surface of the inner difference between both.
If the volume of a confined gas is doubled while the temperature remain constant, what change (if any) would be observed in the pressure
Answers
The gas will obey Boyles Law:
P1 V1 = P2 V2 where P1 and V1 are the original pressure and volume and P2 and V2 are the new values.
If V2 = 2V1 (given) then:
P1 V1 = P2 *2 V1
P2 = P1 V1 / 2V1
P2 = P1 / 2
In other words the pressure is halved. (answer).
What is the best description for a solution with a hydroxide-ion concentration equal to 1 x 10-4m?
Answers
Answer:
Basic solution.
Explanation:
∵ pOH = -log[OH⁻] = - log(1.0 x 10⁻⁴) = 4.
∵ pH + pOH = 14.
∴ pH = 14 - pOH = 14 - 4 = 10.
Since, the pH of the solution is 10 (> 7) and the concentration of [OH⁻] is 1.0 x 10⁻⁴ (> 1.0 x 10⁻⁷) is a basic solution.
Answer:
The solution is basic
Explanation:
Given:
Concentration of OH- = 1*10⁻⁴ m
To determine:
The nature of the solution i.e. acidic or basic
Formula:
A solution where the pH = 7 is neutral
pH < 7 is acidic
pH > 7 is basic
[tex]p[OH] = -log[OH-] = -log[1*10^{-4}] = 4\\ \\p[H] + p[OH] = 14\\\\Therefore\ pH = 14 - p[OH] = 14 - 4 = 10[/tex]
Since, pH > 7, the solution is basic
A chemist dissolves 660.mg of pure hydroiodic acid in enough water to make up 300.mL of solution. Calculate the pH of the solution. Round your answer to 3 significant decimal places.
Answers
The pH of the solution formed by dissolving 660 mg of hydroiodic acid in 300 mL of water was calculated to be approximately 1.765. This was determined by finding the molarity of the hydroiodic acid, which is a strong acid, and using the formula for pH, which is the negative logarithm of the molar concentration of hydronium ions.
Explanation:The subject of this question relates to the calculation of the pH of a solution formed by dissolving hydroiodic acid in water. Hydroiodic acid is a strong acid, meaning it completely ionizes in water. The number of moles of hydroiodic acid is found by converting the mass of the acid (660 mg, or 0.660 g) into moles, with the molar mass of hydroiodic acid as 128 g/mol. This results in approximately 0.00516 moles of hydroiodic acid.
Next, we find the concentration of the acid in the solution by dividing the number of moles by the volume of the solution in liters (0.300 L). This gives a molarity of approximately 0.0172 M. Since hydroiodic acid is a strong acid, the concentration of hydronium ions ([H3O+]) is effectively equal to the concentration of the acid.
Finally, we calculate the pH of the solution using the formula pH = -log[H3O+]. Substituting the found hydronium ion concentration into this formula gives a pH of approximately 1.765.
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A hypothesis is a statement that can be tested through a scientific investigation. What is the purpose of writing a hypothesis?
Answers
Final answer:
Writing a hypothesis serves to provide a testable and falsifiable prediction that connects theoretical ideas to empirical evidence, guiding experimental design and advancing scientific understanding.
Explanation:
The purpose of writing a hypothesis is to make a testable prediction about a natural phenomenon that arises from an initial observation. By establishing a hypothesis, scientists can create a bridge between theoretical ideas and the real world, allowing them to conduct experiments and gather data.
A well-formulated hypothesis must be grounded in scientific knowledge, be logical, and most importantly, be both testable and falsifiable. This means it must be possible to design an experiment or make observations that could potentially disprove the hypothesis if it is not correct.
Scientific investigations commonly begin with an observation that leads to a question. Research and reasoning based on scientific knowledge then guide the formation of a hypothesis, often taking the form 'If condition X occurs, then effect Y will follow'.
This predictive statement is crucial for guiding the experimental design, where the objective is to either support or refute the hypothesis.
Contrary to a hypothesis, a scientific theory is a thoroughly tested and confirmed explanation for a set of observations, and a scientific law is a statement that summarizes the relationship between variables without offering the 'why' of the phenomenon.
If a substance changes color, what has most likely happened
Answers
Final answer:
A substance changing color typically indicates a chemical change where new substances with different properties, including color, are formed. This is attributable to a variety of factors including temperature, light exposure, and the molecular structure of the substance.
Explanation:
When a substance changes color, it is often an indication that a chemical change has occurred. This change is a result of a new substance being formed with different properties, including color. An example of this is when increasing concentration in a chemical reaction causes a color change from orange to brown, illustrating a reaction's progression.
Factors that can cause a substance to change color include a change in temperature, light, and chemical composition. A clear example is provided by the difference in coloration: 1,2-diphenylethene is colorless, whereas its extended conjugation counterpart, 1,10-diphenyl-1,3,5,7,9-decapentaene, shows a yellow-orange color. Such changes in color can be due to differences in energy levels associated with electronic transitions in the molecules.
Color changes in reactions can also be time-dependent, as seen with substances like acetophenone, which change color after prolonged exposure to air or heat.
In summary, color changes are a significant visual clue that a chemical reaction may have taken place. There are four visual clues that indicate this: color change, gas production, formation of a precipitate, and energy transfer.
When a single 1-gram piece of zinc is added to 3 M hydrochloric acid at 25°C, the reaction is slow. Which procedure would most likely increase the rate of the reaction if the reaction were repeated? A. using 1 gram of powdered zinc B. using 1 M hydrochloric acid C. decreasing the temperature to 20.°C D. decreasing the concentration of the zinc
Answers
Answer: option A, using 1 gram of powdered zinc.
Explanation:
The rate of chemical reactions are affected by a number of factors, which you can summarize in this form:
1) Concentration of the reactants
The more concentrate are the reactants, more frequently they will interact (collide) and will be able to yield product. So, the higher the concentration the higher the rate.
This means using 1 M hydrochloric acid, as the option B states, instead of 3 M (stated for the original reaction) will slow down the reaction instead of increase the rate.
The same is valid for the option D. Decreasing the concentration of zinc will not increase the rate of the reaction, but will decrease it.
2) Surface area of the reactants
Increasing the surface area will permit that the reactants reach a faster intimate contact, occurring more of collisions per unit of time, and, consequently increasing the rate of the reaction.
Then, option A, using 1 gram of powdered zinc, i.e. the same amount stated for the original reaction, but with more surface area, will produce the desired effect of increasing the rate of reaction.
3) Temperature
Higher temperatures means that the kinetic energies of the reactants are higher and so the collisions will occur with more energy and the probability of effective collisions will increase. Decreasing the temperature will have the opposite effect (the rate of reaction will decrease).
Hence, the option C, decreasing the temperature to 20° C will not increanse the rate of the reaction.
3) Catalyst
Catalyst ares substances that modify the path of the reaction, decreasing the activation energy and, consequently, increasing the rate of reaction. Since, none of the statements indicates the use of catalyst, this is not an option.
The correct option is A. using 1 gram of powdered zinc.
To understand why using powdered zinc would most likely increase the rate of the reaction, one must consider the factors that affect reaction rates. These factors include the concentration of reactants, the surface area of reactants, the temperature at which the reaction occurs, and the presence of a catalyst.
In this case, the reaction between zinc and hydrochloric acid can be represented by the following equation:
[tex]\[ \text{Zn}(s) + 2\text{HCl}(aq) \rightarrow \text{ZnCl}_2(aq) + \text{H}_2(g)[/tex]
Now, let's analyze each option:
A. Using 1 gram of powdered zinc: Increasing the surface area of the zinc by using it in powdered form would increase the number of particles that can react with the hydrochloric acid at any given time. This would increase the rate of the reaction because more collisions between the zinc and hydrochloric acid molecules would occur, leading to a faster reaction rate.
B. Using 1 M hydrochloric acid: Decreasing the concentration of hydrochloric acid from 3 M to 1 M would actually decrease the rate of the reaction. According to the collision theory, a higher concentration of reactants leads to more frequent collisions and thus a faster reaction rate.
C. Decreasing the temperature to 20°C: Generally, decreasing the temperature would decrease the kinetic energy of the particles, leading to fewer successful collisions and a slower reaction rate. The Arrhenius equation shows that the rate constant \(k\) is directly related to the temperature [tex]T[/tex] by the equation [tex](k = A \cdot e^{-\frac{E_a}{RT}}\)[/tex], where [tex]\(A\)[/tex] is the pre-exponential factor, [tex]\(E_a\)[/tex] is the activation energy, and [tex]R[/tex] is the gas constant.
D. Decreasing the concentration of the zinc: This option would decrease the rate of the reaction for the same reason as option B. A lower concentration of zinc would mean fewer zinc particles are available to react with the hydrochloric acid, resulting in a slower reaction rate.
Therefore, the most effective way to increase the rate of the reaction, based on the given options, is to increase the surface area of the zinc by using it in powdered form, which corresponds to option A.
What type of reaction is the digestion of solid copper wire by nitric acid?
Answers
Copper nitrate and nitric oxide are produced in this reaction.
The digestion of copper wire by nitric acid is a redox reaction producing copper(II) nitrate, nitrogen dioxide, and water. The resulting copper salts are blue in solution.
The digestion of solid copper wire by nitric acid is a type of redox reaction.
When copper metal reacts with concentrated nitric acid, it forms aqueous copper(II) nitrate, accompanies by the release of brown fumes of nitrogen dioxide (NO₂) and water. This chemical reaction is influenced by factors such as concentration of the acid, the metal's activity, and temperature. With concentrated nitric acid, copper generally reduces the acid to nitrogen dioxide.
In a redox reaction, there is a transfer of electrons between the reacting species, with one substance being oxidized (losing electrons) and the other being reduced (gaining electrons).
For the reaction of copper with concentrated nitric acid, the balanced chemical equation would reflect the formation of Cu(NO₃)₂ and NO₂, which can be represented as follows after balancing:
Cu(s) + 4HNO₃(aq) → Cu(NO₃)₂(aq) + 2NO₂(g) + 2H₂O(l).
Copper salts, such as Cu(NO₃)₂, are characterized by a blue color in solution, which indicates the presence of copper(II) ions that have emerged from the copper metal.
Explain how fossils can give information about past environmental conditions. Give at least two examples. Answer using complete sentences.
Answers
Fossils are vital for understanding past environments, indicating past climates and geological events through their preservation conditions. Index fossils help correlate rock layers, while stable isotopes and molecular clocks provide details on the environment and evolutionary relationships.
Fossils provide valuable information about past environmental conditions due to their unique nature as the remains or impressions of ancient life forms. As organisms are fossilized, they can offer clues about the climate, geography, and biological interactions of their time.
Examples of Environmental Clues from Fossils
Fossils and Past Climates: Certain fossils, such as those of tropical plant species, indicate the region once had a warm climate. Conversely, fossils of organisms known to live in colder conditions suggest cooler climates in the past.Fossils and Geological Events: The presence of marine fossils on mountain tops indicates that the mountains were once under the sea, demonstrating geological uplift and plate tectonics.The conditions required for fossilization - such as rapid burial and lack of oxygen - help explain why fossils are rare. When these specific conditions are met, organisms can be preserved in various forms like petrifications, molds, casts, or even preserved traces like footprints.
Index fossils, which are fossils of organisms that were geographically widespread but limited to a short span of geologic time, are particularly useful in correlating rock layers and understanding the history of life on Earth.
Utilizing Fossil Data
By analyzing stable isotopes found in fossils or employing relative and absolute dating methods, scientists can reconstruct past environments and understand the broader ecological context. Molecular clocks, which compare genetic differences to estimate the times when different species diverged, help clarify evolutionary relationships, offering a more complete picture of life's history. However, 'carbon dating' is only applicable for dating relatively recent fossils, as the half-life of carbon-14 is about 5,730 years, which limits its utility for much older specimens.
A solution of SO2 in water contains 0.00023 g of SO2 per liter of solution. What is the concentration of SO2 in ppm? in ppb?
Answers
Answer:
= 230 ppb
Explanation:
Considering that;
1ppm = 1mg/L
Then;
0.00023g = 0.23mg
Therefore;
0.00023 g/L = 0.23 mg/L
0.23 mg/L = 0.23 ppm
1 ppm = 100 ppb
Therefore;
0.23 ppm = 0.23 ×1000
= 230 ppb
Answer:
0.23 ppm , 230 ppb
Explanation:
1 ppm (parts per million) is equivalent to 1 mg of SO₂ in 1 L of the water
Given mass of SO₂ = 0.00023 g = 0.00023 x 1000 mg (1g = 1000 mg) = 0.23 mg
So 0.23 mg/ L = 0.23 ppm
1 ppb (parts per billion) (10⁹) = 1000 ppm (parts per million) (10⁶)
0.23 ppm x 1000 = 230 ppb
How does the negative control of the lac operon by glucose function through inducer exclusion? See Section 18.3 (Page 373) . View Available Hint(s) How does the negative control of the lac operon by glucose function through inducer exclusion? See Section 18.3 (Page 373) . High glucose concentrations prevent the transport of lactose into the cell. High glucose concentrations promote the transport of lactose into the cell. High lactose concentrations prevent the transport of glucose into the cell. High lactose concentrations promote the transport of glucose into the cell.
Answers
Answer:
High glucose concentrations prevent the transport of lactose into the cell.
Explanation:
Which of the following equilibria will shift toward formation of more products if the volume of a reaction mixture at equilibrium increases by a factor of 2? a. 2 SO2(g)+ O2(g) 2 SO3(g) b. NO(g) + O3(g) NO2(g) + O2(g) c. 2N2O5(g) 4 NO2(g)+ O2(g) d. N2O4(g) 2 NO2(g)
Answers
Answer:
The correct answers are:
c. 2N₂O₅(g) ⇄ 4 NO₂(g)+ O₂(g), andd. N₂O₄(g) ⇄ 2 NO₂(g)Explanation:
Following Le Chatelier's principle, when a chemical equilibrium is disturbed by an external force, the reaction will shift toward the side that permits to overcome or minimize the disturbance and comeback to a new equilibrium.
Since, the pressure is inversely related to the volume (the greater the volume the lower the pressure and viceversa), ff the volume of a reaction mixture at equilibrium increases by a factor of 2, the pressure of the system will decrease.
Since, the pressure is directly related to the number of particles (atoms,or molecules), you can predict that the reaction will shift to the side where more molecules are produced to overcome the decrease in the pressure generated by the increase on the volume.
Let's see each option.
a. 2 SO₂(g)+ O₂(g) ⇄ 2 SO3(g)
Incorrect.
There are more molecules on the left side (reactant side) so the reverse reaction is favored. This is the equilibrium will shift to the formation of more reactants. So, this is an incorrect option.
b. NO(g) + O₃(g) ⇄ NO₂(g) + O₂(g)
Incorrect.
There are two molecules in the reactant side and two molecules in the product side. Hence, in this equilibrium the increase of volume will not yield a change in the equlibrium.
c. 2N₂O₅(g) ⇄ 4 NO₂(g)+ O₂(g)
Correct.
In this reaction, there are four molecules in the product side (right) against 2 molecules in the reactant side (left). So, the increase in volume will produce a shift toward the product side.
d. N₂O₄(g) ⇄ 2 NO₂(g)
Correct.
There are more molecules in the product side than in the reactant side, so you predict a shift toward the formation of more product to overcome the increase of volume.
Enter a balanced chemical equation for the reaction between potassium metal and liquid water.
Answers
Answer:
2K (s) + 2H₂O (l) → 2KOH (aq) + H₂(g)↑Explanation:
1) Word equation (given)
Potassium + water → ?2) Kind of reaction
Potassium is an alkali metal.This is a single replacement reaction.
Alkali metals is the group of metals in the group 1 of the periodic table. These are the most active metals, meaning that they react violently with water releasing hydrogen gas.
Alkali metals can lose an electron to form compounds with oxidation number +1.The general equation for the reaction of an alkali metal and water is:Metal + Water → hydroxide + gaseous hydrogen
X + H₂O → XOH(aq) + H₂ (g) ↑
3) Chemical equation
K (s) + H₂O (l) → KOH(aq) + H₂(g)↑4) Balance
2K (s) + 2H₂O (l) → 2KOH(aq) + H₂(g)↑There is the same number of each atom on both sides: 2 K in the left and in the right, 4 H in the left and in the right, and 2 oxygen in the left and in the right. So, the equation is balanced.
The reaction of potassium metal with water produces potassium hydroxide and hydrogen gas, represented by the balanced chemical equation [tex]2K(s) + 2H_2O(l) \rightarrow 2KOH(aq) + H_2(g)[/tex]
The balanced chemical equation for the reaction between potassium metal (K) and liquid water (H2O) is:
[tex]2K(s) + 2H_2O(l) \rightarrow 2KOH(aq) + H_2(g)[/tex]
In this reaction, potassium metal reacts vigorously with water to produce potassium hydroxide (KOH), which is an alkali, and hydrogen gas ([tex]H_2[/tex]). This is an exothermic reaction and heat is also released. The products include the aqueous potassium hydroxide and gaseous hydrogen. The equation is balanced with two atoms of potassium and two molecules of water on the reactant side, and two formula units of potassium hydroxide and one molecule of hydrogen gas on the product side.
Data: Beaker Test 1:Temp/VolBeaker Test 2:Temp/VolBeaker Test 3:Temp/VolBeaker Test 4:Temp/VolBeaker Test 5:Temp/VolTrial One: Air-14.5 °C / 4.3 mL0.9 °C / 4.7 mL21.7°C / 5.0 mL48.5 °C / 5.4 mL81.2 °C / 5.9 mLTrial Two: Nitrogen (N2)-14.5 °C / 4.4 mL0.9 °C / 4.7 mL21.7 °C / 5.1 mL48.5 °C / 5.4 mL81.2 °C / 5.9 mLData Analysis: Create a separate graph of temperature vs. volume for each of the gas samples. You are encouraged to use graphing software or online tools to create the graphs; be sure to take screenshots of the graphs that also include your data.Make sure to include the following on your graphs:•Title•Labels for axes and appropriate scales•Clearly plotted data points
Answers
A particular device uses electromagnetism by using electricity to move magnets. The magnets in this device are then used to do work. Which device uses electromagnetism in this way?
Answers
a solenoid is used wherever a magnetic field is needed
Answer:
Electric motor
Explanation:
An electric motor is such a device which works on the principle of electro magnetism. When current is allowed to pass through the wire in the electric motor, it creates a magnetic field around the coil.
This magnetic field causes a force that pushes the magnets placed around the coil that moves or spins the magnets which results in the working of the motor. Thus in this way electric motor uses electromagnetism by using electricity in the coil to move the magnets which in turn does the useful work.
The average kinetic energy of the particles of a substance _____.
A.is equal to the total energy absorbed by the substance
B. increases as the temperature of the substance is lowered
C. is directly proportional to the temperature of the substance
D. is not affected by the temperature of the substance
Answers
Answer:
C
Explanation:
The higher the temperatures the higher the kinetic energy of the particles. This is because the particles move more rapidly and faster with increased temperatures. This is why the more you heat a substance it changes phases as it molecules/particles move more rapidly and collide with more force.
The average kinetic energy of the particles of a substance is directly proportional to the temperature of the substance (Option C).
Kinetic energy refers to the form of energy of an object due to its motion (movement).Kinetic energy is directly proportional to the motion of its constituent particles, which depends on the temperature (higher temperature higher motion).Conversely, potential energy refers to the energy stored by an object because of its position with regard to other objects.Kinetic energy cannot be negative, but potential energy can be negative.In conclusion, the average kinetic energy of the particles of a substance is directly proportional to the temperature of the substance (Option C).
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Draw the correct structure of the indicated product for each of the following reactions.
Answers
To draw the structure of each reaction first determine the product of the reaction and then draw the structure by using the line formula method.
What is a product?In chemistry, the word product refer to the substance or substances after a reaction. For example in the reaction H2+O = H2O, the product is water (H2O).
How to draw the structure of a product?Determine the product: Bear in mind that the product or products have the same atoms and number of atoms as the reactants.Draw the structure: One simple way to do this is by using the line formula method that involves representing carbons with lines and other products along these. Below you find an example.Note: This question is incomplete; due to this, I answered it based on general knowledge.
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How many ml of 0.0500 m cacn2 are needed to make 25.0 ml of 0.0150 m solution? The molar mass of cacn2 is 80.11 g/mol.
Answers
Answer:
= 7.50 mL
Explanation:
m1v1=m2v2
In this case;
m1=0.05
m2=0.015 and
v2=25.00mL
Therefore;
(.0500M)(v1)=(25.00mL)(.0150M)
V1 = ((25.00mL)(0.0150M))/0.0500 M
= 7.50 mL
The reaction 2 no(g) + cl2(g) → 2 nocl(g) is carried out in a closed vessel. if the partial pressure of no is decreasing at a rate of 184 torr/min, what is the rate of change of the total pressure in the vessel? the sign of the answer is important.
Answers
Answer:
92.0 torr/min.
Explanation:
For the reaction: 2NO(g) + Cl₂(g) → 2NOCl(g).∵ The rate of the reaction = - 1/2(ΔP)NO/Δt = - (ΔP)Cl₂/Δt = 1/2(ΔP)NOCl/Δt.
∵ (ΔP)NO/Δt = - 184 torr/min.
∴ The rate of change of the total pressure in the vessel = - 1/2(ΔP)NO/Δt = (- 1/2)(- 184 torr/min) = 92.0 torr/min.
A 75.0-mL volume of 0.200 M NH3 (Kb=1.8×10−5) is titrated with 0.500 M HNO3. Calculate the pH after the addition of 15.0 mL of HNO3.
Answers
The pH IS 9.6
Explanation;Moles NH3 initially present = 0.0750 L X 0.2 mol/L = 0.015 mol NH3
Moles HNO3 added = 0.015 L X 0.500 mol/L = 7.5X10^-3 mol HNO3 added
NH3 + HNO3 --> NH4+ + NO3-
So, after the addition, the solution contains 7.50X10^-3 mol NH4+ and 9.5X10^-3 mol NH3. The concentrations are:
[NH4+] = 7.5X10^-3 mol / 0.090 L = 0.0833 M
[NH3] = 1,5X10^-2mol / 0.090 L = 0.1667 M
The equilbirium involved is:
NH3 + H2O <--> NH4+ + OH-
Kb = [NH4+][OH-]/[NH3] = 1.8X10^-5
1.8X10^-5 = (0.0833)[OH-]/0.1667
[OH-] = 3.602 X10^-5
pOH = 4.44
pH = 14.00 - pOH
= 9.557 or 9.6
what is the ultimate end of a high mass star that has a core about 2.8x the mass of our sun?
A. a pulsar
B. a black hole
C. a brown dwarf
D. a magnetar
Answers
Answer:
A
Explanation:
It is formed after the star has ended its star cycle into a supernova. The star collapsed into a neutron star that is smaller than the progenitor star but has inherited angular momentum. IT, therefore, spins faster emitting electromagnetic radiation that seems to pulsate.
Answer:
A) Pulsar
Explanation:
Pulsars are collapsed cores of stars usually supergiant stars
this happens when a supernova leaves behind the star core that has no outer protection layer of high gravity so the core collapses in on itself to create a very high magnitude star and also has trillions more mass.
Write equations showing how each of the following weak bases ionizes water to form OH-.
a.) CO3^2-. Express your answer as a chemical equation.
b.) C6H5NH2. Express your answer as a chemical equation.
c.) C2H5NH2. Express your answer as a chemical equation.
Answers
Bases produce OH- when they react with water.
A weak base is a substance that ionizes only to a small extent in water. A weak base remains largely undissociated in water. Recall that bases produce OH- in solution.
The equation of the reaction by which the following species produce OH- in water are shown below;
CO3^2-(aq) + H2O(l) -------> HCO2^-(aq) + OH^-(aq)
C6H5NH2(aq) + H2O(l) -------> C6H5NH3^+(aq) + OH^-(aq)
C2H5NH2(aq) + H2O(l) -------> C2H5NH3^+(aq) + OH^-(aq)
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The weak bases CO3^2-, C6H5NH2 and C2H5NH2 ionize in water by accepting a proton (H+) from water, and in the process, creating hydroxide ions (OH-) and their corresponding positive ions. The respective ionization equations are: CO3^2- + H2O ⟶ HCO3- + OH-, C6H5NH2 + H2O ⟶ C6H5NH3+ + OH-, and C2H5NH2 + H2O ⟶ C2H5NH3+ + OH-.
Explanation:The ionization of weak bases in water involves the base accepting a proton (H+) from water, creating hydroxide ions (OH-) and a corresponding positive ion. Here are the equations representing how the three given bases ionize in water:
CO3^2-: CO3^2- + H2O ⟶ HCO3- + OH- C6H5NH2 (Aniline): C6H5NH2 + H2O ⟶ C6H5NH3+ + OH-C2H5NH2 (Ethylamine): C2H5NH2 + H2O ⟶ C2H5NH3+ + OH-Note that in all these reactions, OH- is formed showing the formation of basic solutions.
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The discovery of the electron as a subatomic particle was a result of
Answers
The discovery of the electron as a subatomic particle was a result of experiments with cathode ray tubes.
J.J. Thomson discovered the electron, the first subatomic particle in 1897. He used discharged tube experiments.
The electricity was passed through gases at low pressure which resulted in the emission of cathode rays. This discovery was made in his experiments with Cathode ray tubesIn this experiment, he discovered that atoms had negatively charged bodies called electronsThus, the discovery of the electron as a subatomic particle was a result of experiments with cathode ray tubes.
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What color does red and yellow make?
Answers
Red and yellow make orange.
Red and yellow mix together to create the color orange.
When you mix red and yellow, you are essentially combining their respective pigments or light wavelengths.
Red has a longer wavelength and is a primary color, meaning it cannot be made by combining other colors. On the other hand, yellow, which is a primary hue as well, has a medium wavelength.
The color orange is perceived as a new color when red and yellow are combined. This occurs as a result of the red pigment's or wavelength's stimulation of our eyes' long-wavelength receptors and the yellow pigment's or wavelength's stimulation of our eyes' medium-wavelength receptors. The brain interprets the mix of inputs as the color orange after processing the data from these receptors.
When red and green light are combined at their maximum intensity in the RGB (Red, Green, Blue) color model, they produce yellow rather than orange. Red and yellow combine to form orange in the subtractive color model, which is the one utilized for physical pigments like paint. This is caused by variations in how light and pigments interact to create perceptions of color.
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What forces must be overcome for a substance to melt
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Intermolecular forces.
Which statement does NOT apply to unsaturated hydrocarbons?
Unsaturated hydrocarbons require energy to react.
Unsaturated hydrocarbons are very reactive.
Unsaturated hydrocarbons contain double and triple bonds.
Unsaturated hydrocarbons undergo addition reactions to become saturated.
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Unsaturated hydrocarbons undergo addition reactions to become saturated.
Answer: The correct statement is unsaturated hydrocarbons require energy to react.
Explanation:
Unsaturated hydrocarbons are defined as the hydrocarbons which have double or triple covalent C-C bonds. They are known as alkenes and alkynes respectively. The general formula for these hydrocarbons is [tex]C_nH_{2n}[/tex] and [tex]C_nH_{2n-2}[/tex]
These hydrocarbons are more reactive than the saturated ones because of the presence of [tex]\pi-[/tex]bonds. These bonds are weaker than [tex]\sigma-[/tex]bonds and thus can be easily broken. Addition reactions is more favorable for the compounds having [tex]\pi-[/tex]bonds.
These hydrocarbons do not require any energy to react. They are readily reactive.
Hence, the correct statement is unsaturated hydrocarbons require energy to react.
Calculate [H+] for each of the following solutions, and indicate whether the solution is acidic, basic, or neutral.
Part A [OH−]= 4.5×10−4 M . Express your answer using two significant figures.
Part B 1) the solution is acidic 2) the solution is basic 3) the solution is neutral
Part C [OH−]= 7.7×10−9 M . Express your answer using two significant figures.
Part D 1) the solution is acidic 2) the solution is basic 3) the solution is neutral
Part E A solution in which [OH−] is 140 times greater than [H+]. Express your answer using two significant figures.
Part F 1) the solution is acidic 2) the solution is basic 3) the solution is neutral
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Answer:
Part A: 10.7.
Part B: 2) the solution is basic.
Part C: 5.9.
Part D: 1) the solution is acidic.
Part E: 8.1.
Part F: 2) the solution is basic.
Explanation:
Part A [OH−]= 4.5×10−4 M . Express your answer using two significant figures.
∵ [H₃O⁺][OH⁻] = 10⁻¹⁴.
[OH⁻] = 4.5×10⁻⁴ M.
∴ [H₃O⁺] = 10⁻¹⁴/[OH⁻] = 10⁻¹⁴/(4.5×10⁻⁴ M) = 2.22 × 10⁻¹¹ M.
∵ pH = - log[H₃O⁺]
∴ pH = - log(2.22 × 10⁻¹¹) = 10.65 ≅ 10.7.
Part B 1) the solution is acidic 2) the solution is basic 3) the solution is neutral
The solution is basic, because the pH is higher than 7.
Part C [OH⁻]= 7.7×10⁻⁹ M . Express your answer using two significant figures.
∵ [H₃O⁺][OH⁻] = 10⁻¹⁴.
[OH⁻] = 7.7×10⁻⁹ M.
∴ [H₃O⁺] = 10⁻¹⁴/[OH⁻] = 10⁻¹⁴/(7.7×10⁻⁹ M) = 1.29 × 10⁻⁶ M.
∵ pH = - log[H₃O⁺]
∴ pH = - log(1.29 × 10⁻⁶) = 5.88 ≅ 5.9.
Part D 1) the solution is acidic 2) the solution is basic 3) the solution is neutral
The solution is acidic, because the pH is lower than 7.
Part E A solution in which [OH−] is 140 times greater than [H+]. Express your answer using two significant figures.
∵ [H₃O⁺][OH⁻] = 10⁻¹⁴.
∵ [OH⁻] = 140[H₃O⁺]
∴ [H₃O⁺](140[H₃O⁺]) = 10⁻¹⁴.
∴ 140 [H₃O⁺]² = 10⁻¹⁴.
[H₃O⁺]² = 10⁻¹⁴/ 140 = 7.14 x 10⁻¹⁷.
∴ [H₃O⁺] = √(7.14 x 10⁻¹⁷) = 8.45 x 10⁻⁹ M.
∵ pH = - log[H₃O⁺]
∴ pH = - log(8.45 x 10⁻⁹) = 8.07 ≅ 8.1.
Part F 1) the solution is acidic 2) the solution is basic 3) the solution is neutral
The solution is basic, because the pH is higher than 7.
The [H+] for solutions with given [OH−] are calculated using the ion product of water, with solutions having [H+] less than 1.0 × 10-7 being basic and those with more being acidic. The solutions for Part A and E were found to be basic while the solution for Part C was found to be acidic.
Explanation:The [H+] of a solution can be determined from its [OH−] by using the ion product of water, which is 1.0 × 10-14 at 25°C. This can be represented by the equation [H+][OH−] = 1.0 × 10-14.
For Part A, you needed to calculate [H+] for a solution with [OH−] = 4.5 × 10-4M. [H+] = 1.0 × 10-14 / [OH−] = 1.0 × 10-14 / 4.5 × 10-4= 2.2 × 10-11 M. Since [H+] is less than 1.0 × 10-7, the solution is basic.
For Part C, [OH−] is 7.7 × 10-9M. [H+] = 1.0 × 10-14 / 7.7 × 10-9= 1.3 × 10-6M. Because [H+] is higher than 1.0 × 10-7, the solution is acidic.
In Part E, the solution's [OH−] is 140 times that of [H+]. Therefore, if we let [H+] = x, we get [OH−] = 140x. Since [H+][OH−] = 1.0 × 10-14, we get x(140x) = 1.0 × 10-14. Solving for x, we get [H+] = x = 5.37 × 10-14M. Since [H+] is less than 1.0 × 10-7, the solution is basic.
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The transfer of a phosphate group to a molecule or compound is called
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Answer: Phosphorylation
can you mark me as brainiest please?In the lab, you are thirsty and would like a drink. Can you use the beaker as a cup?
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No you can’t do that, that’s idiotic
At what temperature (hot or cold) can we dissolve a gas in a solution
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Depends on the gas and grams of solute. If you were able to give me a gas i would be able to help you but i cannot without the gas or chemical makeup.