What are the top ten most abundant elements in the human body
1. Oxygen
2. Carbon
3. Hydrogen
4. Nitrogen
5. Calcium
6. Phosphorus
7. Potassium
8. Sodium
9. Chlorine
10. Magnesium
Answer:
1. Oxygen
2. Carbon
3. Hydrogen
4. Nitrogen
5. Calcium
6. Phosphorus
7. Potassium
8. Sodium
9. Chlorine
10.Sulfer
Explanation:
All of the covalent carbon-carbon bonds in unsaturated hydrocarbons share 2 pairs of electrons.
True
False
False. carbon-carbon bonds that share 2 pairs of electrons are double bonds. An unsaturated hydrocarbon isnt necessary to only have double bonds. they can also have single bonds or triple bonds.
Answer: The given statement is false.
Explanation:
An unsaturated hydrocarbon is a chain of carbon and hydrogen atoms in which adjacent carbon atoms are attached together through double or triple bond.
Since it is known that carbon atom forms covalent compounds so, an unsaturated hydrocarbon not only contains double or triple bonds it also has single bonds in between.
Thus, we can conclude that the statement all of the covalent carbon-carbon bonds in unsaturated hydrocarbons share 2 pairs of electrons, is false.
DOUBLE POINTS!! What causes a reaction to be spontaneous? Provide an example in your explanation.
Thanks in advance! :) GIVING BRAINLIEST!
A chemical reaction is considered spontaneous if A) the reaction releases heat, and B) if the entropy of the system increases. There is a formula known as the Gibbs Free Energy equation that predicts whether or not a reaction will be spontaneous; this formula considers the enthalpy side (heat) and the entropy side (disorder) of the reaction when making the prediction.
Hope this helps!
A reaction is spontaneous if it can occur without external input, determined by the changes in enthalpy and entropy of the system. This is calculated using the Gibbs free energy equation. An example is the combustion of gasoline.
Explanation:A reaction is considered spontaneous if it can proceed without any outside intervention. This is determined by two key factors: change in enthalpy (∆H) and change in entropy (∆S). The Gibbs free energy change (ΔG) equation, ΔG = ΔH - TΔS, is used to determine spontaneity. For a reaction to be spontaneous, ΔG has to be negative (exergonic reaction).
For instance, the combustion of gasoline is an example of a spontaneous reaction. When gasoline is ignited, it combusts (reacts with oxygen) to create water and carbon dioxide, releasing heat and expanding gases, driving your car forward. This reaction is spontaneous because it releases energy (∆H is negative) and the products are more disordered than the reactants (∆S is positive), making ∆G negative.
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the human body needs 120 grams of glucose (c6h12o6) everyday to do cellular respiration and provide you with atp energy for metabolism if you ate only pizza (with a meat topping) you would need to eat 20 slices of pizza per day ( 1 slice contains about 6 grams of glucose) to fill your body ls requirement for glucose how many moles of glucose are required
please show work thank you
The molar mass of glucose is 180.16g/mol. So to convert grams of glucose into moles of glucose, divided the mass in grams by the molar mass, and grams will cancel out leaving you with moles. 120g / 180.16 g/mol = 0.666 moles
the Ksp for BaCO3 is 5.1x10^-9. how many grams of BaCO3 will dissolve in 1000ml of water
Answer:
= 0.014 g of BaCO3
Explanation:
Let x = mol/L of BaCO3 that dissolve.
This will give;
x mol/L Ba2+ and x mol/L CO32-
But;
Ksp = 5.1x10^-9.
Therefore;
Ksp = 5.1 x 10^-9 = (x)(x)
Thus;
x = molar solubility
= √ (5.1 x 10^-9)
= 7.1 x 10^-5 M
Therefore;
Mass BaCO3 = 7.1 x 10^-5 M x 1 L x 197.34 g/mol
= 0.014 g
The mass of BaCO3 that dissolves in 1000 ml of water is 0.014 g.
What is Ksp?The term Ksp shows the extent of dissolution of a substance in solution. In this case we are told in the question that the Ksp of the BaCO3 is 5.1x10^-9. Recall that the mass that dissolve is 1000 mL of water is the solubility of the solute.
Ksp = [Ba^2+] [CO3^2-] = x^2
x =√ Ksp
x = √5.1x10^-9
x = 7.14 * 10^-5 M
moles = concentration * volume
Mass/molar mass = concentration * volume
Mass = concentration * volume * molar mass
Mass = 7.14 * 10^-5 M * 1 L * 197 g/mol
Mass = 0.014 g
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The standard gibbs free energy of formation of ___ is zero: 1. h2o(l) 2. na(s) 3. h2 (g)
3. H2 (g) has a standard gibbs free energy of 0
The standard Gibbs free energy of formation is zero for substances in their standard states. Hence, it would be zero for Sodium (Na) as a solid and Hydrogen (H2) as a gas. However, for water (H2O), it is not zero as it is a compound formed from hydrogen and oxygen.
Explanation:The subject of your question pertains to the standard Gibbs free energy of formation. By definition, the standard Gibbs free energy of formation of an element in its most stable form is zero under standard conditions. In your question, you offer three options: water (H2O), sodium (Na), and hydrogen (H2).
Since the standard Gibbs free energy of formation is the change that happens when one mole of a substance forms from its elements in their standard states, the standard Gibbs free energy of formation for an elemental substance in its standard state, is zero. Therefore, Sodium (Na) in its standard state as a solid (s) and Hydrogen (H2) in its gaseous state (g) both have a standard Gibbs free energy of formation of zero.
In contrast, water (H2O) is a compound, not an element. Thus, its standard Gibbs free energy of formation is not zero because it does not exist in nature in its elemental form but is formed via reactions between hydrogen and oxygen.
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PLEASE HELP!!! WILL AWARD 50 POINTS!!!!
The answer should be C because the reactants should come to power of three.
Answer:
C
Explanation:
Which oxide is Mn2O3?
Manganese Oxide?????
Manganese oxide is a blackish/ brown solid and the primary natural source of manganese. Oxide compounds are not conductive to electricity.
the answer is Manganese Oxide (Mn2O3)
Which of the following is true about catalysts?
A Catalysts increase the number of collisions that occur between reactants.
B Catalysts increase the activation energy by forming new reactants.
C Catalysts reduce the potential energy of the compounds that are produced.
D Catalysts reduce the energy needed for the reaction to take place.
Answer:
D
Explanation:
Catalysts lower the activation energy of the reactants so the reaction proceeds faster than naturally. The catalyst does not change the reaction (the potential energy of the reaction remains the same) in any other way and is not caused by the reaction.
Answer: Option (D) is the correct answer.
Explanation:
A catalyst is defined as the substance which lowers the activation energy of a chemical reaction without itself getting consumed in the reaction so that there will be increase in rate of reaction.
As catalyst, basically lowers the activation energy so that reactant molecules with lower energy can also participate in the reaction. Hence, more number of collisions can occur due to which there is rapid formation of products.
Thus, we can conclude that the statement catalysts reduce the energy needed for the reaction to take place, is true about catalysts.
Determine the celsius temperature of 2.49 mol of gas contained in a 1.00 l vessel
Answer:
= -266.24°C
Explanation:
According to ideal gas law;
PV = nRT, where P is pressure, V is the volume, n is the number of moles, R is the ideal gas constant and T is the temperature.
PV = nRT
T = PV/(nR)
= 143 kPa * (1atm/101.325 kPa) * 1.00L / (2.49 mol * 0.08206 Latm/molK)
= 6.91 K
= -266.24°C
To find out the temperature of the gas in Celsius, we must use the ideal gas law, input known values, solve for temperature in Kelvin and then convert to Celsius.
Explanation:The given question seeks to determine the temperature of a gas contained in a specific volume, based on the number of moles of the gas. As such, we will need to use the ideal gas law PV=nRT - where P is pressure, V is volume, n is the number of mols, R is the ideal gas constant, and T is temperature. For our calculation, we will use the standard pressure of 1 atm and an ideal gas constant value of 0.0821 L atm/mol · K.
The ideal gas law rearranges to T = PV/nR. With pressure P being 1 atm, volume V being 1 L and n being 2.49 mol, we get T = (1 atm x 1 L) / (2.49 mol x 0.0821 L atm/mol · K). After performing the calculation, you need to remember that the resulting temperature will be in Kelvin. As a final step, to convert temperature from Kelvin to Celsius, we subtract 273.15 from our result.
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Which of the following solutions is a good buffer system?A solution that is 0.10 M HCN and 0.10 M NaClA solution that is 0.10 M HCN and 0.10 M LiCNA solution that is 0.10 M HNO3 and 0.10 M KNO3A solution that is 0.10 M NaOH and 0.10 M HNO3A solution that is 0.10 M NaCl and 0.10 M HCl
Answer:
A solution that is 0.10 M HCN and 0.10 M LiCN
Explanation:
A good buffer system contains a weak acid and its salt or a weak base and its salt. In this case; A solution that is 0.10 M HCN and 0.10 M LiCN, would make a good buffer system. HCN is a weak acid, while LiCN is a salt of the weak acid, that is, CN- conjugate of the acid.What element is not grouped with others in a family?What is its usual atomic structure
Noble gases is the answer, located on the far left of the periodic table; hopes this helps.
A 2.0 molal sugar solution has approximately the same freezing point as 1.0 molal solution of 1) CaCl2 2) CH3COOH 3) NaCl 4) C2H5OH
Answer:
3) NaCl.
Explanation:
∵ ΔTf = iKf.m
where, i is the van 't Hoff factor.
Kf is the molal depression freezing constant.
m is the molality of the solute.
The van 't Hoff factor is the ratio between the actual concentration of particles produced when the substance is dissolved and the concentration of a substance as calculated from its mass.
For most non-electrolytes dissolved in water, the van 't Hoff factor is essentially 1.
So, for sugar: i = 1.
∴ ΔTf for sugar = iKf.m = (1)(Kf)(2.0 m) = 2 Kf.
For most ionic compounds dissolved in water, the van 't Hoff factor is equal to the number of discrete ions in a formula unit of the substance.
For NaCl, it is electrolyte compound which dissociates to Na⁺ and Cl⁻.
So, i for NaCl = 2.
∴ ΔTf for NaCl = iKf.m = (2)(Kf)(1.0 m) = 2 Kf.
So, the right choice is: 3) NaCl.
Explain how two two parents with brown skin could have a child with dark brown skin and anotherchild with light brown skin
one of the parents (or both of them) could be a carrier for the allele of light brown skin if the brown skin is the dominant gene. so if both of the parents are carriers of the gene for the light brown skin, then theres a small chance that their child could have light brown skin
Consider the following equilibrium reaction having gaseous reactants and products.
4HCl + O2 ⇌ 2H2O + Cl2
Which of the following would result from increasing the volume of hydrochloric acid?
The volume of oxygen increases.
The volume of chlorine decreases.
The volume of water vapor increases.
The rate of backward reaction increases.
Answer:
The volume of water vapor increases.
Explanation:
Pressure, concentration, and temperature all affect the equilibrium position of chemical reactions in a closed system such as this one. Increasing HCl increases the pressure in the system. It favors the forward's reaction because this favors a reduced overall pressure in the system. The products have a combined 3 moles of gases while the reactants have a combined 5 moles of gases.
Answer:
The concentration of water vapor increases
Explanation:
I just got this right on the test
When selecting small wares to use in the kitchen, a manager must be sure the small wares are durable, easy to clean, safe, and ?
In addition to being durable, easy to clean, and safe, kitchen small wares should also be efficient. They should enhance productivity, be of the right size, and function effectively to suit the cooking requirements and kitchen’s capacity.
Explanation:When selecting small wares for use in the kitchen, a manager must ensure these items are not only durable, easy to clean, and safe, but also efficient. Efficient here means that they should enhance productivity in the kitchen. For example, a knife should be sharp enough to reduce the time and effort in chopping. A pot or pan should have a good heat conduction for fast and even cooking. In this aspect, stainless steel, cast iron, and copper are often preferred. Besides, they should be of the right size to comply with the cooking requirements and kitchen’s capacity.
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When selecting small wares to use in the kitchen, a manager must be sure the small wares are durable, easy to clean, safe, and functional.
When selecting small wares for the kitchen, a manager must ensure that the items are not only durable, easy to clean, and safe but also functional. Functionality refers to the ability of the small wares to perform their intended tasks efficiently and effectively. This means that the items should meet the specific needs of the kitchen staff, be ergonomically designed to minimize strain and injury, and contribute to the overall productivity of the kitchen operations. Functional small wares are essential for a smooth and efficient workflow in a kitchen setting.
The complete question is:
When selecting small wares to use in the kitchen, a manager must be sure the small wares are durable, easy to clean, safe, and ______?
A group of students are studying the magnetic field of Earth. Which of these layers of Earth interact to create Earth's magnetic field?
A)crust and core
B)mantle and crust
C)mantle and inner core
D)outer core and inner core
Answer:
D
Explanation:
The inner core (which is solid) is the hottest layer of the earth. It, therefore, contributes to heating up the outer core. The outer core is liquid and rotation of the earth (Coriolis effect) causes the molten rocks to swirl like a tornado. Because the outer core is mostly made of metals, that have lost electrons and hence charged (due to the enormous heat), the swilring effect causing an electric effect. This consequently causes the dynamo effect that creates a magnetic field. This magnetic field covers the earth and protects it from harmful radiation from the solar storms.
Answer:
the answer is d
Explanation:
;-;
Identify the principal role of cellular respiration. to convert solar energy into the chemical energy of sugars to convert the chemical energy of sugars into heat to maintain an elevated body temperature to convert kinetic energy into the chemical energy of sugars to convert the chemical energy of sugars into the chemical energy that fuels life's processes
Answer: A. To convert the chemical energy of sugars into the chemical energy that fuels life's processes
Explanation:
The main role of cellular respiration is to convert the chemical energy of sugars into the chemical energy that fuels the processes of life.
• The main function of cellular respiration is to offer the cells with the energy, which they need to work appropriately.
• It is the process in which catabolic reactions are used to dissociate down the food into usable energy so that the cells and the living species can use them and survive.
• It is the process by which the living things combine oxygen with the molecules of the food, and convert the chemical energy present in that substances into the the form of energy that helps in sustaining life.
Thus, the main function of cellular respiration is to convert the chemical energy of sugars into the chemical energy that fuels the processes of life.
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What is formed when two or more atoms join together chemically
A molecule is formed
Lithium has been found to be especially effective in the treatment of
i know if ur talking about medications then its usually prescribed for people with depression and anxiety
Can someone check my work?
Electromagnetic waves Mechanical Waves
Visible Light Ocean Wave
Can be reflected Requires a medium
Infrared light Sound
Speed dependent on
the medium
Both
Transfers energy
Longitudinal wave
Transverse wave
Answer:
Electromagnetic:
Infrared light
Visible Light
Both:
Transfers energy
Transverse wave
Can be reflected
Speed dependent upon the medium they are traveling through
Mechanical:
Requires a medium
Ocean wave
Longitudinal wave
Sound
Explanation:
yeah
Three 6−l flasks, fixed with pressure gauges and small valves, each contain 6 g of gas at 276 k. flask a contains ch4, flask b contains he, and flask c contains h2. rank the flask contents in terms of:
First, please check the missing part in your question in the attachment.
a) So first, the Rank of pressure:
according to this formula PV = nRT and when n = m/Mw
PV = m/Mw * R*T
when we have the same mass m and the same V volume so P will proportional with the mole weight M as when the M is smaller the pressure will be greater
when Mw of H2(A) = 2 g / Mw of He (B) = 4 g and Mw of CH4(C) = 16 g
∴ Pressure :
(A) > (B) > (c)
B) The rank of average molecular kinetic energy:
when K = 3/2 KB T
when K is the average kinetic energy per molecule of gas
and KB is Boltzmann's constant
and T is the temperature (K)
So from this equation, we can know that K only depends on T value, and when we have the T constant here for A, B, and C So the rank of K will be like the following:
∴ A = B = C
C) the rank of diffusion rate after the valve is opened:
according to this formula:
R2/R1 = √M1/M2
from this equation, we can see that diffusion is proportional to the reciprocal of the molecular mass M so,
when Mw H2 (A) = 2 g & Mw He(B) = 4 g & CH4 (C) = 16 g
∴ the rank of diffusion:
A > B > C
D) The rank of the Total kinetic energy of the molecules:
when we have the Mw different so it will make the no.of molecules differs as when the Mw is low the no.of molecules will be hight, and when the average molecular kinetic energy equals. so the total kinetic energy will depend on no. of molecules
∵ Mw A < Mw B < Mw C
∴no .of molecules of A > B >C
∴ the rank of total kinetic energy is:
A > B > C
e) the rank of density:
when ρ = m/ v
and m is the mass & v is the volume and we have both is the same for A, B, and C
so the density also will be the same, ∴ the rank of the density is:
A = B = C
F) the rank of the collision frequency:
as the no.of molecules increase the collision frequency increase and depend also on the velocity and it's here the same.
∴ Collision frequency will only depend on the no.of molecules
we have no.of molecules of A > B > C as Mw A < B < C
∴the rank of the collision frequency is:
A > B > C
An aqueous solution at 25°C has a OH− concentration of 1.9x10−8M . Calculate the H3O+ concentration. Be sure your answer has the correct number of significant digits.
Answer:
= 5.26 × 10^-7 M
Explanation:
We know that;
[H3O+][OH-] = 1 x 10^-14
Therefore;
Given; OH− concentration = 1.9x10^−8 M
Then; [H3O+] = (1 x 10^-14)/[OH-]
= (1 x 10^-14)/(1.9x10^−8)
= 5.26 × 10^-7 M
Taking into account the definition of pH and pOH, the concentration of H₃O⁺ is 5.25×10⁻⁷ M.
pHFirst of all, pH is a measure of acidity or alkalinity that indicates the amount of hydrogen ions present in a solution or substance.
The pH is defined as the negative base 10 logarithm of the activity of hydrogen ions, that is, the concentration of hydrogen ions or H₃O⁺:
pH= - log [H⁺]= - log [H₃O⁺]
pOHSimilarly, pOH is a measure of hydroxyl ions in a solution and is expressed as the logarithm of the concentration of OH⁻ ions, with the sign changed:
pOH= - log [OH⁻]
Relationship between pH and pOHThe following relationship can be established between pH and pOH:
pOH + pH= 14
This caseIn this case, [OH⁻]= 1.9×10⁻⁸ M. Then, the pOH can be calculated as:
pOH= - log (1.9×10⁻⁸ M)
Solving:
pOH= 7.72Now, you can calculated the pH, considering the relationship between pH and pOH:
pOH + pH= 14
7.72 + pH=14
pH=14 - 7.72
pH= 6.28Finally, the concentration of H₃O⁺ can be calculated from the definition of pH:
pH= - log [H₃O⁺]
6.28= - log [H₃O⁺]
[H₃O⁺]= 10⁻⁶ ²⁸
[H₃O⁺]= 5.25×10⁻⁷ MIn summary, the concentration of H₃O⁺ is 5.25×10⁻⁷ M.
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A car starts from rest and uniformly accelerates to a speed of 30 mi/h in 6 s. The car moves north the entire time. Which option correctly lists a vector quantity from the scenario?
speed: 30 mi/h
acceleration: 5 mi/h/s north
distance: 30 mi
velocity: 5 mi/h/s north
Answer:
acceleration: 5 mi/h/s north
Explanation:
A quantity can be either vector quantity or scalar quantity, a vector quantity is a quantity with both magnitude and direction while a scalar quantity has magnitude only.
Examples of vector quantities include; velocity, acceleration, displacement , etc.
Acceleration is the rate of change of an object's velocity per unit of time. It is given by the formula; Velocity/time
Therefore in this case; a = 30 mi/h /6 s
= 5 mi/h/s
Therefore;
Acceleration = 5 mi/h/s
A substance in a specific state of matter has a definite volume but it does not have a rigid structure. Which of following could be another characteristic of the substance? It is highly compressible. It also has a definite shape. Its particles move randomly at high speeds. Its intermolecular forces can be partially overcome.
Answer: Its intermolecular forces can be partially overcome.
Explanation:
Solid state : In this state, the molecules are arranged in regular and repeating pattern. They have fixed shape and fixed volume. The molecules are closely packed that means they are fixed and vibrate in place but they can not move from one place to another. They are in compressible.
For example : Copper
Liquid state : In this state, the molecules are present in random and irregular pattern. They have fixed volume but take the shape of the container. The molecules are closely packed but they can move from one place to another and thus intermolecular forces can be overcome. They are less compressible.
For example : water
Gaseous state : In this state, the molecules are present in irregular pattern. They have neither fixed shape nor volume.The molecules are not closely packed and they can move randomly at high speeds. They are highly compressible.
For example : Helium gas
The longest continuous chain of carbons is called the ______________.2. An organic compound containing only hydrogen and carbon is called a/an ______________.3. Sometimes an organic formula is written with a/an ______________, which is a shorthand notation that represents a hydrocarbon side chain.4. A hydrocarbon compound that contains multiple bonds is said to be a/an ______________.5. Some molecules have the same chemical formula but a different bonding pattern. These molecules are referred to as ______________.6. A hydrocarbon that contains only single bonds is called a/an ______________.7. An aromatic ring structure with the formula of C6H6 is called ______________.8. Ethene is an example of a/an ______________.9. The cis and trans isomers are also called ______________ because their atoms are arranged differently with respect to their double bonds.
Final answer:
The terms such as 'parent hydrocarbon chain', 'hydrocarbon', and 'unsaturated' describe the structural aspects of organic molecules, while 'isomers', 'alkane', 'benzene', and 'alkene' are types of molecules distinguished by their bonding patterns or specific structures.
Explanation:
The longest continuous chain of carbons is called the parent hydrocarbon chain.
An organic compound containing only hydrogen and carbon is called a hydrocarbon.
Sometimes an organic formula is written with a substituent group notation, which is a shorthand notation that represents a hydrocarbon side chain.
A hydrocarbon compound that contains multiple bonds is said to be unsaturated.
Some molecules have the same chemical formula but a different bonding pattern. These molecules are referred to as isomers.
A hydrocarbon that contains only single bonds is called a alkane or saturated hydrocarbon.
An aromatic ring structure with the formula of C6H6 is called benzene.
Ethene is an example of a alkene.
The cis and trans isomers are also called geometric isomers because their atoms are arranged differently with respect to their double bonds.
What is the ph of a solution that is .75 m in sodium acetate and .50 m in acetic acid? (ka for acetic acid is 1.8*10^-5?
Answer:
4.921.
Explanation:
It is an acidic buffer solution;∵ pH = pKa + log[salt]/[acid].
∴ pH = - log(1,8 x 10⁻⁵) + log[0.75/0.50] = 4.745 + 0.1761 = 4.921.
The pH of a solution that is 0.75 M in sodium acetate and 0.50 M in acetic acid can be calculated using the Henderson-Hasselbalch equation, resulting in a pH of approximately 4.916.
Explanation:The pH of a solution that is 0.75 M in sodium acetate (CH3COONa) and 0.50 M in acetic acid (CH3COOH) can be calculated using the Henderson-Hasselbalch equation, which relates the pH, pKa, and the ratio of the concentrations of the anion of the acid to the acid itself. Since sodium acetate is a salt that dissociates completely in solution, the concentration of acetate ions (CH3COO-) will be the same as the concentration of sodium acetate, which is 0.75 M. The pKa is the negative logarithm of the Ka value for acetic acid, which is given as 1.8 × 10-5. Calculating pKa gives us:
pKa = -log(1.8 × 10-5) = 4.74
Now, applying the Henderson-Hasselbalch equation:
pH = pKa + log(·])
pH = 4.74 + log(·(0.50))
Upon calculating the logarithmic term, we find that the pH of the solution is:
pH = 4.74 + log(1.5)
pH = 4.74 + 0.176
pH = 4.916
The pH of this acetate buffer solution is approximately 4.916.
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What is the percent composition of carbon in heptane c7h16
Answer: the percent composition of carbon in heptane is 83.9%
Explanation:
1) Atomic masses of the atoms:
C: 12.01 g/molH: 1.008 g/mol2) Molar mass of heptane:
C₇H₁₆: 7 × 12.01 g/mol + 16×1.008 g/mol = 100.2 g/mol3) Mass of carbon in one mole of heptane:
C₇: 7 × 12.01 g/mol = 84.07 g/mol3) Percent composition of carbon:
% = (mass in grams of C) / (mass in grams of C₇H₁₆) × 100 == (84.07 g/ 100.2 g) × 100 = 83.9% ← answer
Rank the following elements by effective nuclear charge, Zeff, for a valence electron.F LI Be B N
1.The effective nuclear charge (Zeff or Z*) is the net positive charge experienced by an electron in a multi-electron atom. The term “effective” is used because the shielding effect of negatively charged electrons prevents higher orbital electrons from experiencing the full nuclear charge.
Equation: Zeff = Z – S
2.where Z is the number of protons
3. S is the number of electrons between the nucleus and the electron in question.
Decreasing order effective nuclear charge:
F>N>B>Be>Li
Answer: F>N>B>Be>Li
Explanation: Electrons are attracted towards the nucleus due to the positive charge present in the nucleus and negative charge on the electrons. This nucleus charge for all the electrons present in different shells of an atom is not same. Inner electrons decreases the nuclear charge felt by the outer shell electrons and its known as shielding effect.
Effective nuclear charge is calculated using the formula:
[tex]Z_e_f_f=Z-S[/tex]
where, [tex]Z_e_f_f[/tex] stands for effective nuclear charge, Z is the atomic number and S is the shielding constant value which is calculated using Slater's rule.
As per Slater's rule, the contribution by the electrons in nth shell is 0.35 and
the contribution by the electrons present in n-1 shell is 0.85 and for rest of the shells like n-2, n-3 etc it is 1.00. It is also 1.00 for the n-1 shell electrons that are present in d and s.
Electron configurations for all the elements we have are:
Li = [tex]1s^22s^1[/tex]
Be = [tex]1s^22s^2[/tex]
B = [tex]1s^22s^22p^1[/tex]
N = [tex]1s^22s^22p^3[/tex]
F = [tex]1s^22s^22p^5[/tex]
The number of inner shell electrons is equal for all these elements so for the valence electrons the shielding constant would almost be same.
So, effective nuclear charge will be greater for the element to which the atomic number is higher.
The order of atomic numbers is F>N>B>Be>Li . So, the highest to lowest order of effective nuclear charge will also be F>N>B>Be>Li .
What form the ideal gas law would you use to calculate the temperature of a gas
Final answer:
The ideal gas law is used to calculate the temperature of a gas by using the equation PV = nRT, where P is the pressure, V is the volume, n is the number of moles, R is the ideal gas constant, and T is the temperature in Kelvin.
Explanation:
The ideal gas law is used to calculate the temperature of a gas. The ideal gas law is a single equation that relates the pressure, volume, temperature, and number of moles of an ideal gas. The formula to calculate the temperature of a gas using the ideal gas law is:
PV = nRT
Where:
P is the pressure of the gasV is the volume of the gasn is the number of moles of the gasR is the ideal gas constantT is the temperature of the gas, measured in KelvinBy rearranging the ideal gas law equation and solving for T, you can calculate the temperature of a gas.