Question 1

Calculate the molecular mass, in g/mol, of C6H12O6.

Accepted Answer

Question 2

How many silicon atoms are there in 1.00 g of silicon?

Accepted Answer

A) 1 atom 
B) 0.0356 atoms 
C) 2.57 * 1023 atoms 
D) 2.14 * 1022 atoms 
E) 1.75 * 1025 atoms 
A) 1 atom 
B) 0.0356 atoms 
C) 2.57 * 1023 atoms 
D) 2.14 * 1022 atoms 
E) 1.75 * 1025 atoms

Question 3

Balance the following chemical equation:
H2 + N2 $\rarr$ NH3

Accepted Answer

Question 4

How many moles of phosphine (PH3 )are produced for every 4.0 moles of hydrogen that react according to the chemical equation below?
3H2 + P2 $\rarr$ 2PH3

Accepted Answer

Question 5

Determine the number of moles of water produced by the reaction of 155 g of ammonia and 356 g of oxygen.
4NH3 + 5O2 $\rarr$ 4NO + 6H2O

Accepted Answer

Question 6

How many grams of Cr can be produced by the reaction of 44.1 g of Cr2O3 with 35.0 g of Al according to the following chemical reaction?
 2Al + Cr2O3 $\rarr$Al2O3 + 2Cr

Accepted Answer

A) 7.56 g 
B) 30.2 g 
C) 67.4 g 
D) 104 g 
E) None of these. 
A) 7.56 g 
B) 30.2 g 
C) 67.4 g 
D) 104 g 
E) None of these.

Question 7

Calculate the molecular mass of potassium permanganate, KMnO4.

Accepted Answer

A) 52 amu 
B) 70 amu 
C) 110 amu 
D) 158 amu 
E) 176 amu 
A) 52 amu 
B) 70 amu 
C) 110 amu 
D) 158 amu 
E) 176 amu

Question 8

Solid sodium hydrogen carbonate (also known as sodium bicarbonate)can be decomposed to form solid sodium carbonate, gaseous carbon dioxide, and water vapor. When the balanced chemical reaction for this process is written such that the coefficient of water is 1, what is the coefficient of carbon dioxide?

Accepted Answer

A) 0 
B) 1 
C) 2 
D)    
E) cannot be determined 
A) 0 
B) 1 
C) 2 
D)    
E) cannot be determined

Question 9

How many grams of silver nitrate are necessary to react completely with 7.000 moles of copper?
Cu + 2 AgNO3 $\rarr$Cu(NO3 )2 + 2 Ag

Accepted Answer

Question 10

A gold wire has a diameter of 1.00 mm. What length of this wire contains exactly 1.00 mol of gold? (density of Au = 17.0 g/cm3)

Accepted Answer

A) 2630 m 
B) 3.69 m 
C) 251 m 
D) 14.8 m 
E) 62.7 m 
A) 2630 m 
B) 3.69 m 
C) 251 m 
D) 14.8 m 
E) 62.7 m

Question 11

How many atoms are in 0.0728 g of PCl3?

Accepted Answer

A) 1.28 * 1021 atoms 
B) 4.38 * 1022 atoms 
C) 4.39 * 1021 atoms 
D) 3.19 * 1020 atoms 
E) 6.02 * 1024 atoms 
A) 1.28 * 1021 atoms 
B) 4.38 * 1022 atoms 
C) 4.39 * 1021 atoms 
D) 3.19 * 1020 atoms 
E) 6.02 * 1024 atoms

Question 12

Liquid heptane, C7H16, burns in oxygen gas to yield carbon dioxide and water. What mass of water is produced when 15.0 mL of heptane burns completely? (density of heptane = 0.6838 g/mL)

Accepted Answer

A) 14.8 g 
B) 2.70 g 
C) 31.6 g 
D) 1.85 g 
E) 21.6 g 
A) 14.8 g 
B) 2.70 g 
C) 31.6 g 
D) 1.85 g 
E) 21.6 g

Question 13

Calculate the molecular mass of ethylene glycol, C2H6O2, a compound frequently used as automobile antifreeze.

Accepted Answer

Question 14

How many O atoms are there in 51.4 g CaSO4?

Accepted Answer

A) 4 
B) 2.40 * 1024 
C) 1.13 
D) 9.09 * 1023 
E) 2.28 * 1023 
A) 4 
B) 2.40 * 1024 
C) 1.13 
D) 9.09 * 1023 
E) 2.28 * 1023

Question 15

An atom of bromine has a mass about four times greater than that of an atom of neon. Which choice makes the correct comparison of the relative numbers of bromine and neon atoms in 1,000 g of each element?

Accepted Answer

A) The number of bromine and neon atoms is the same. 
B) There are one thousand times as many bromine atoms as neon atoms. 
C) There are one thousand times as many neon atoms as bromine atoms. 
D) There are four times as many neon atoms as bromine atoms. 
E) There are four times as many bromine atoms as neon atoms. 
A) The number of bromine and neon atoms is the same. 
B) There are one thousand times as many bromine atoms as neon atoms. 
C) There are one thousand times as many neon atoms as bromine atoms. 
D) There are four times as many neon atoms as bromine atoms. 
E) There are four times as many bromine atoms as neon atoms.

Question 16

The percent composition by mass of an unknown chlorinated hydrocarbon was found to be 37.83% C, 6.35% H, and 55.83% Cl by mass.What is the empirical formula of this compound?

Accepted Answer

A) C2H4Cl 
B) C3H7Cl 
C) C3H6Cl2 
D) C4H9Cl 
E) C5H11Cl 
A) C2H4Cl 
B) C3H7Cl 
C) C3H6Cl2 
D) C4H9Cl 
E) C5H11Cl

Question 17

What is the molar mass of nicotine, C10H14N2?

Accepted Answer

A) 134 g/mol 
B) 148 g/mol 
C) 158 g/mol 
D) 210 g/mol 
E) 162 g/mol 
A) 134 g/mol 
B) 148 g/mol 
C) 158 g/mol 
D) 210 g/mol 
E) 162 g/mol

Question 18

Calculate the mass of excess reagent remaining at the end of the reaction in which 90.0 g of SO2 are mixed with 100.0 g of O2. 2SO2 + O2 $\rarr$2SO3

Accepted Answer

A) 11.5 g 
B) 22.5 g 
C) 67.5 g 
D) 77.5 g 
E) 400 g 
A) 11.5 g 
B) 22.5 g 
C) 67.5 g 
D) 77.5 g 
E) 400 g

Question 19

One way of obtaining pure sodium carbonate is through the decomposition of the mineral trona, Na5(CO3)2(HCO3)$\rarr$2H2O, as shown in the following reaction: 2Na3(CO3)(HCO3)$\rarr$2H2O(s)$\rarr$ 3Na2CO3(s)+ CO2(g)+ 5H2O(g)
When 15 metric ton (1 *103 kg)of trona is decomposed, 11 metric ton of Na2CO3 is recovered. What is the percent yield of this reaction? (1 metric ton = 103 kg)

Accepted Answer

A) 95% 
B) 73% 
C) 65% 
D) 42% 
E) 13% 
A) 95% 
B) 73% 
C) 65% 
D) 42% 
E) 13%

Question 20

Which of the following statements are true about a sample of sulfur and a sample of oxygen if the two samples are of equal mass?

Accepted Answer

A) The number of electrons in the two samples is about the same. 
B) The number of protons in the two samples is about the same. 
C) The number of atoms in the two samples is about the same. 
D) There are roughly twice as many sulfur atoms as oxygen atoms. 
E) There are roughly twice as many oxygen atoms as sulfur atoms. 
A) The number of electrons in the two samples is about the same. 
B) The number of protons in the two samples is about the same. 
C) The number of atoms in the two samples is about the same. 
D) There are roughly twice as many sulfur atoms as oxygen atoms. 
E) There are roughly twice as many oxygen atoms as sulfur atoms.

Exam 3: Mass Relationships in Chemical Reactions

Calculate the molecular mass, in g/mol, of C6H12O6.

How many silicon atoms are there in 1.00 g of silicon?

Balance the following chemical equation: H2 + N2 →\rarr→ NH3

How many moles of phosphine (PH3 )are produced for every 4.0 moles of hydrogen that react according to the chemical equation below? 3H2 + P2 →\rarr→ 2PH3

Determine the number of moles of water produced by the reaction of 155 g of ammonia and 356 g of oxygen. 4NH3 + 5O2 →\rarr→ 4NO + 6H2O

How many grams of Cr can be produced by the reaction of 44.1 g of Cr2O3 with 35.0 g of Al according to the following chemical reaction? 2Al + Cr2O3 →\rarr→ Al2O3 + 2Cr

Calculate the molecular mass of potassium permanganate, KMnO4.

How many grams of silver nitrate are necessary to react completely with 7.000 moles of copper? Cu + 2 AgNO3 →\rarr→ Cu(NO3 )2 + 2 Ag

A gold wire has a diameter of 1.00 mm. What length of this wire contains exactly 1.00 mol of gold? (density of Au = 17.0 g/cm3)

How many atoms are in 0.0728 g of PCl3?

Liquid heptane, C7H16, burns in oxygen gas to yield carbon dioxide and water. What mass of water is produced when 15.0 mL of heptane burns completely? (density of heptane = 0.6838 g/mL)

Calculate the molecular mass of ethylene glycol, C2H6O2, a compound frequently used as automobile antifreeze.

How many O atoms are there in 51.4 g CaSO4?

An atom of bromine has a mass about four times greater than that of an atom of neon. Which choice makes the correct comparison of the relative numbers of bromine and neon atoms in 1,000 g of each element?

The percent composition by mass of an unknown chlorinated hydrocarbon was found to be 37.83% C, 6.35% H, and 55.83% Cl by mass.What is the empirical formula of this compound?

What is the molar mass of nicotine, C10H14N2?

Calculate the mass of excess reagent remaining at the end of the reaction in which 90.0 g of SO2 are mixed with 100.0 g of O2. 2SO2 + O2 →\rarr→ 2SO3

Which of the following statements are true about a sample of sulfur and a sample of oxygen if the two samples are of equal mass?

Chemistry: The Study of Change

Atoms, Molecules, and Ions

Reactions in Aqueous Solution

Gases

Thermo-Chemistry

Quantum Theory and the Electronic Structure of Atoms

Periodic Relationships Among the Elements

Chemical Bonding I: Basic Concepts

Chemical Bonding Ii: Molecular Geometry and Hybridization of Atomic Orbitals

Intermolecular Forces and Liquids and Solids

Physical Properties of Solutions

Chemical Kinetics

Chemical Equilibrium

Acids and Bases

Acid-Base Equilibria and Solubility Equilibria

Chemistry in the Atmosphere

Entropy, Free Energy, and Equilibrium

Electrochemistry

Metallurgy and the Chemistry of Metals

Nonmetallic Elements and Their Compounds

Transition Metal Chemistry and Coordination Compounds

Nuclear Chemistry

Organic Chemistry

Synthetic and Natural Organic Polymers

Filters

Calculate the molecular mass, in g/mol, of C₆H₁₂O₆.

Balance the following chemical equation: H₂ + N₂ $\rarr$ NH₃

How many moles of phosphine (PH₃)are produced for every 4.0 moles of hydrogen that react according to the chemical equation below? 3H₂ + P₂ $\rarr$ 2PH₃

Determine the number of moles of water produced by the reaction of 155 g of ammonia and 356 g of oxygen. 4NH₃ + 5O₂ $\rarr$ 4NO + 6H₂O

How many grams of Cr can be produced by the reaction of 44.1 g of Cr₂O₃ with 35.0 g of Al according to the following chemical reaction? 2Al + Cr₂O₃ $\rarr$ Al₂O₃ + 2Cr

Calculate the molecular mass of potassium permanganate, KMnO₄.

How many grams of silver nitrate are necessary to react completely with 7.000 moles of copper? Cu + 2 AgNO₃ $\rarr$ Cu(NO₃)₂ + 2 Ag

A gold wire has a diameter of 1.00 mm. What length of this wire contains exactly 1.00 mol of gold? (density of Au = 17.0 g/cm³)

How many atoms are in 0.0728 g of PCl₃?

Liquid heptane, C₇H₁₆, burns in oxygen gas to yield carbon dioxide and water. What mass of water is produced when 15.0 mL of heptane burns completely? (density of heptane = 0.6838 g/mL)

Calculate the molecular mass of ethylene glycol, C₂H₆O₂, a compound frequently used as automobile antifreeze.

How many O atoms are there in 51.4 g CaSO₄?

What is the molar mass of nicotine, C₁₀H₁₄N₂?

Calculate the mass of excess reagent remaining at the end of the reaction in which 90.0 g of SO₂ are mixed with 100.0 g of O₂. 2SO₂ + O₂ $\rarr$ 2SO₃