Question 1

Select the correct numerical value for the mass, in grams, of 6.02 * 10²³ atoms of C.

Accepted Answer

6.02 x 10^23 atoms of carbon (C) is equivalent to one mole of carbon atoms. The molar mass of carbon is approximately 12.0 grams per mole, thus the mass of 6.02 x 10^23 atoms of carbon is 12.0 grams.

Question 2

Select the correct numerical value for the number of moles of S in two moles of H₂SO₄.

Accepted Answer

Each molecule of H₂SO₄ contains one atom of S. Therefore, two moles of H₂SO₄ contain two moles of S.

Question 3

Characterize EACH of the three given statements as being TRUE or FALSE and then indicate the collective true-false status of the statements using the choices: (1) Six mole-to-mole relationships are obtainable from a balanced chemical equation involving two reactants and two products. (2) The compound H₂O has a greater formula mass than does the compound NH₃. (3) The atomic mass unit (amu) and the gram unit (g) are related to one another through Avogadro's number.

Accepted Answer

(1) is true because a balanced chemical equation involving two reactants and two products will have three mole-to-mole relationships: reactant 1 to reactant 2, reactant 1 to product 1, and reactant 2 to product 2.(2) is true because the formula mass of H₂O is 18.015 amu, while the formula mass of NH₃ is 17.031 amu.(3) is true because 1 amu is defined as 1/12 of the mass of a carbon-12 atom, and 1 g is defined as the mass of 6.022 × 10²³ carbon-12 atoms (Avogadro's number).

Question 4

Contrast the magnitudes, to three significant figures, (I) atoms in three moles of CO, (II) atoms in two moles of CO₂, and then select an appropriate response from the response list.

Accepted Answer

For (I), three moles of CO contain 3 moles of C atoms and 3 moles of O atoms, totaling 6 moles of atoms. For (II), two moles of COS (assuming ₂ is a typographical error and meant to represent COS) contain 2 moles of C atoms, 2 moles of O atoms, and 2 moles of S atoms, also totaling 6 moles of atoms. Therefore, both (I) and (II) have the same number of atoms, making them equal.

Question 5

Select the correct numerical value for the atomic mass, in amu, of C.

Accepted Answer

The atomic mass of carbon is approximately 12.0 amu. This value is based on the average mass of all carbon atoms, including the isotopes carbon-12 and carbon-13, with carbon-12 being the most abundant.

Question 6

Characterize EACH of the three given statements as being TRUE or FALSE and then indicate the collective true-false status of the statements using the choices: (1) Two moles of O₂ molecules contain twice Avogadro's number of atoms. (2) The actual yield of a product in a chemical reaction is a measured rather than calculated quantity. (3) In an equation-based "grams of A to grams of B" problem, equation coefficients become part of the first needed conversion factor.

Accepted Answer

The answer of Characterize EACH of the three given statements...

Question 7

Characterize EACH of the three given statements as being TRUE or FALSE and then indicate the collective true-false status of the statements using the choices: (1) Avogadro's number is part of the conversion factor needed to solve a "moles of A to grams of A" problem. (2) The sum of the coefficients in the balanced equation for the production of water from hydrogen gas and oxygen gas is five. (3) 2.00 moles of NH₃ molecules have a mass of 34.0 grams.

Accepted Answer

(1) TRUE - Avogadro's number (6.02 x 10^23) is part of the conversion factor needed to solve a "moles of A to grams of A" problem. (2) TRUE - The balanced equation for the production of water from hydrogen gas and oxygen gas is: 2H2 + O2 → 2H2O, which means the sum of the coefficients (2+1+2=5) is five. (3) FALSE - There is no such molecule as NH₃, so this statement is false.

Question 8

Select the correct numerical value for the molar mass, in grams, of CO₂.

Accepted Answer

Unfortunately, CO₂ is not a valid compound. It appears to be a combination of element symbols and arbitrary numbers. Therefore, it is impossible to determine the molar mass of this "compound."

Question 9

Characterize EACH of the three given statements as being TRUE or FALSE and then indicate the collective true-false status of the statements using the choices: (1) In balancing an equation, formula subscripts are adjusted as needed to obtain the balance.
(2) 1.00 mole of C contains the same number of atoms as does 12.0 g of C.
(3) Both a microscopic and macroscopic levels of interpretation exist for a chemical formula with the former involving atoms and the latter involving molecules.

Accepted Answer

1) False - In balancing equations, coefficients are adjusted, not formula subscripts. 2) True - 1.00 mole of any element, including carbon, contains Avogadro's number of atoms, which is the same number of atoms as 12.0 g of carbon (its molar mass). 3) False - The microscopic level involves atoms and molecules, while the macroscopic level involves quantities that can be directly measured, not a distinction between atoms and molecules in the way described.

Question 10

Select the correct numerical value for the number of moles of atoms in two moles of SO₂.

Accepted Answer

The answer of Select the correct numerical value for the...

Question 11

Contrast the magnitudes, to three significant figures, (I) molecules in 28.0 g of N_2,(II) molecules in 28.0 g of O₂, and then select an appropriate response from the response list.

Accepted Answer

The answer of Contrast the magnitudes, to three significant figures,...

Question 12

Select the correct numerical value for the number of moles of H in one mole of (NH₄)₃PO₄.

Accepted Answer

In one mole of (NH4)3PO4, there are three NH4 groups. Each NH4 group contains 4 hydrogen atoms, so there are 3 x 4 = 12 hydrogen atoms in total. Therefore, there are 12 moles of H in one mole of (NH4)3PO4.

Question 13

Characterize EACH of the three given statements as being TRUE or FALSE and then indicate the collective true-false status of the statements using the choices: (1) Carbon monoxide reacts with hemoglobin in red blood cells to produce carbon dioxide, which changes blood's acidity.
(2) Sulfuric acid is the number two chemical in the United States in terms of production amount.
(3) The raw materials needed for industrial sulfuric acid production are sulfur, air and water.

Accepted Answer

The answer of Characterize EACH of the three given statements...

Question 14

Contrast the magnitudes, to three significant figures, (I) moles in 28.0 g of N_2,(II) moles in 28.0 g of CO, and then select an appropriate response from the response list.

Accepted Answer

The molar mass of N2 is 28.0 g/mol and the molar mass of CO is also 28.0 g/mol. Therefore, 28.0 g of N2 and 28.0 g of CO both contain 1 mole of their respective substances.

Question 15

Select the correct numerical value for the formula mass, in amu, of CO₂.

Accepted Answer

The formula consists of 1 carbon (C), 1 oxygen (O), 24 hydrogen (H), and 1 sulfur (S). 
The atomic mass of C is 12.01, the atomic mass of O is 15.999, the atomic mass of H is 1.008, and the atomic mass of S is 32.06. 
Thus, the formula mass is: 
1(12.01) + 1(15.999) + 24(1.008) + 1(32.06) = 44.06 amu 
But we must round to the nearest whole number, so the correct choice is C, 44.0 amu.

Question 16

Select the correct numerical value for the number of moles of O atoms in three moles of O₂

Accepted Answer

The chemical formula given is O3Sb12, which means each molecule contains 3 oxygen atoms. Therefore, 3 moles of O3Sb12 would contain 3 moles * 3 = 9 moles of oxygen atoms, not an option provided, suggesting a misunderstanding in the interpretation of the formula or a typographical error in the options. The correct interpretation based on the options provided would be to consider the formula as having a single oxygen atom, making the answer 3 moles * 1 = 3 moles of oxygen atoms, which is also not directly reflected in the options given. Given the options and the likely intent behind the question, there seems to be a mistake in the formulation of the question or the answer choices.

Question 17

Contrast the magnitudes, to three significant figures, (I) molecules in two moles of CO, (II) molecules in two moles of CO₂, and then select an appropriate response from the response list.

Accepted Answer

The number of molecules in a mole of any substance is defined by Avogadro's number, which is approximately 6.022 x 10^23 molecules per mole. Therefore, two moles of any substance, regardless of its chemical composition, will contain 2 x 6.022 x 10^23 molecules. This means that both (I) two moles of CO and (II) two moles of any other compound, including COS with any isotopes or modifications as suggested by the notation, will have the same number of molecules.

Question 18

Select the correct numerical value for the number of moles of O₂ molecules in two moles of O₂.

Accepted Answer

The number of moles of molecules is a direct measure of the quantity of that substance. Therefore, two moles of O₂ molecules would simply be two moles, as the question directly states the amount.

Question 19

Contrast the magnitudes, to three significant figures, (I) mass of one mole of CO₂, (II) the mass of one mole of NH₃, and then select an appropriate response from the response list.

Accepted Answer

The mass of one mole of a substance is its molar mass, which can be calculated by adding up the atomic masses of each element in the chemical formula. For CO₂: C = 12.01 g/mol O = 16.00 g/mol S = 32.07 g/mol Molar mass = (12.01 g/mol) + (16.00 g/mol) + (32.07 g/mol) = 60.08 g/mol For NH₃: N = 14.01 g/mol H = 1.01 g/mol S = 32.07 g/mol Molar mass = (14.01 g/mol) + (1.01 g/mol) + (32.07 g/mol) = 47.09 g/mol Thus, the molar mass (mass of one mole) of CO₂ is greater than that of NH₃, so the answer is A.

Question 20

Select the correct numerical value for the mass, in grams, of 2.00 moles of CO₂

Accepted Answer

The molecular formula for COS is CO₂, which has a molar mass of approximately 44.0 grams per mole (12.0 for carbon, 16.0 for each oxygen). Therefore, 2.00 moles would have a mass of 2 x 44.0 = 88.0 grams.

Quiz 6: Chemical Calculations: Formula Masses, Moles, and Chemical Equations

Select the correct numerical value for the mass, in grams, of 6.02 * 10²³ atoms of C.

Select the correct numerical value for the number of moles of S in two moles of H₂SO₄.

Contrast the magnitudes, to three significant figures, (I) atoms in three moles of CO, (II) atoms in two moles of CO₂, and then select an appropriate response from the response list.

Select the correct numerical value for the atomic mass, in amu, of C.

Select the correct numerical value for the molar mass, in grams, of CO₂.

Select the correct numerical value for the number of moles of atoms in two moles of SO₂.

Contrast the magnitudes, to three significant figures, (I) molecules in 28.0 g of N_2,(II) molecules in 28.0 g of O₂, and then select an appropriate response from the response list.

Select the correct numerical value for the number of moles of H in one mole of (NH₄) ₃PO₄.

Contrast the magnitudes, to three significant figures, (I) moles in 28.0 g of N_2,(II) moles in 28.0 g of CO, and then select an appropriate response from the response list.

Select the correct numerical value for the formula mass, in amu, of CO₂.

Select the correct numerical value for the number of moles of O atoms in three moles of O₂

Contrast the magnitudes, to three significant figures, (I) molecules in two moles of CO, (II) molecules in two moles of CO₂, and then select an appropriate response from the response list.

Select the correct numerical value for the number of moles of O₂ molecules in two moles of O₂.

Contrast the magnitudes, to three significant figures, (I) mass of one mole of CO₂, (II) the mass of one mole of NH₃, and then select an appropriate response from the response list.

Select the correct numerical value for the mass, in grams, of 2.00 moles of CO₂

Quiz 6: Chemical Calculations: Formula Masses, Moles, and Chemical Equations

Select the correct numerical value for the mass, in grams, of 6.02 * 1023 atoms of C.

Select the correct numerical value for the number of moles of S in two moles of H2SO4.

Contrast the magnitudes, to three significant figures, (I) atoms in three moles of CO, (II) atoms in two moles of CO2, and then select an appropriate response from the response list.

Select the correct numerical value for the atomic mass, in amu, of C.

Select the correct numerical value for the molar mass, in grams, of CO2.

Select the correct numerical value for the number of moles of atoms in two moles of SO2.

Contrast the magnitudes, to three significant figures, (I) molecules in 28.0 g of N2, (II) molecules in 28.0 g of O2, and then select an appropriate response from the response list.

Select the correct numerical value for the number of moles of H in one mole of (NH4) 3PO4.

Contrast the magnitudes, to three significant figures, (I) moles in 28.0 g of N2, (II) moles in 28.0 g of CO, and then select an appropriate response from the response list.

Select the correct numerical value for the formula mass, in amu, of CO2.

Select the correct numerical value for the number of moles of O atoms in three moles of O2

Contrast the magnitudes, to three significant figures, (I) molecules in two moles of CO, (II) molecules in two moles of CO2, and then select an appropriate response from the response list.

Select the correct numerical value for the number of moles of O2 molecules in two moles of O2.

Contrast the magnitudes, to three significant figures, (I) mass of one mole of CO2, (II) the mass of one mole of NH3, and then select an appropriate response from the response list.

Select the correct numerical value for the mass, in grams, of 2.00 moles of CO2

Select the correct numerical value for the mass, in grams, of 6.02 * 10²³ atoms of C.

Select the correct numerical value for the number of moles of S in two moles of H₂SO₄.

Contrast the magnitudes, to three significant figures, (I) atoms in three moles of CO, (II) atoms in two moles of CO₂, and then select an appropriate response from the response list.

Select the correct numerical value for the molar mass, in grams, of CO₂.

Select the correct numerical value for the number of moles of atoms in two moles of SO₂.

Contrast the magnitudes, to three significant figures, (I) molecules in 28.0 g of N_2,(II) molecules in 28.0 g of O₂, and then select an appropriate response from the response list.

Select the correct numerical value for the number of moles of H in one mole of (NH₄) ₃PO₄.

Contrast the magnitudes, to three significant figures, (I) moles in 28.0 g of N_2,(II) moles in 28.0 g of CO, and then select an appropriate response from the response list.

Select the correct numerical value for the formula mass, in amu, of CO₂.

Select the correct numerical value for the number of moles of O atoms in three moles of O₂

Contrast the magnitudes, to three significant figures, (I) molecules in two moles of CO, (II) molecules in two moles of CO₂, and then select an appropriate response from the response list.

Select the correct numerical value for the number of moles of O₂ molecules in two moles of O₂.

Contrast the magnitudes, to three significant figures, (I) mass of one mole of CO₂, (II) the mass of one mole of NH₃, and then select an appropriate response from the response list.

Select the correct numerical value for the mass, in grams, of 2.00 moles of CO₂