Question 1

What is the molar mass of sulfuric acid (H2SO4)?

Accepted Answer

A) 49.0 g/mol 
B) 24.5 g/mol 
C) 101 g/mol 
D) 98.1 g/mol 
E) 97.0 g/mol 
A) 49.0 g/mol 
B) 24.5 g/mol 
C) 101 g/mol 
D) 98.1 g/mol 
E) 97.0 g/mol

Question 2

The empirical formula for buckminsterfullerene is C1, and its molar mass is 720.6 g/mol. What is its molecular formula?

Accepted Answer

A) C60 
B) C72 
C) C12 
D) C1 
E) C720 
A) C60 
B) C72 
C) C12 
D) C1 
E) C720

Question 3

Caffeine has an elemental analysis of 49.48% carbon, 5.190% hydrogen, 16.47% oxygen, and 28.85% nitrogen. It has a molar mass of 194.19 g/mol. What is the molecular formula of caffeine?

Accepted Answer

A) C4H5N2O 
B) C8H10N4O2 
C) C10H14N2O2 
D) C6H6NO2 
E) C5H7NO 
A) C4H5N2O 
B) C8H10N4O2 
C) C10H14N2O2 
D) C6H6NO2 
E) C5H7NO

Question 4

How many nitrogen atoms are there in 51.0 g of (NH4)2SO4 (ammonium sulfate)?

Accepted Answer

A) 2.32   1023 atoms 
B) 3.07   1025 atoms 
C) 4.65   1023 atoms 
D) 6.14   1025 atoms 
E) 5.39   1023 atoms 
A) 2.32   1023 atoms 
B) 3.07   1025 atoms 
C) 4.65   1023 atoms 
D) 6.14   1025 atoms 
E) 5.39   1023 atoms

Question 5

Phosphorus trichloride reacts with water to form phosphorous acid, H3PO3, and hydrochloric acid in the following unbalanced reaction. For each mole of phosphorous acid produced by this reaction, how many moles of HCl are produced?__ PCl3    __H2O   __H3PO3   + __ HCl

Accepted Answer

A) 1 
B) 2 
C) 3 
D) 4 
E) 5 
A) 1 
B) 2 
C) 3 
D) 4 
E) 5

Question 6

Identify the list below that has these chloride compounds arranged in order of increasing molar mass.

Accepted Answer

A) CCl4   PCl3 
    SCl2   BCl3 
B) SCl2   BCl3   PCl3   CCl4 
C) BCl3   CCl4   PCl3   SCl2 
D) SCl2   BCl3   CCl4   PCl3 
E) BCl3   SCl2   PCl3   CCl4 
A) CCl4   PCl3 
    SCl2   BCl3 
B) SCl2   BCl3   PCl3   CCl4 
C) BCl3   CCl4   PCl3   SCl2 
D) SCl2   BCl3   CCl4   PCl3 
E) BCl3   SCl2   PCl3   CCl4

Question 7

Mesitylene is a liquid hydrocarbon. If 0.115 g of this compound is burned in pure oxygen to give 0.3790 g CO2 and 0.1035 g H2O, what is the empirical formula of the compound?

Accepted Answer

Question 8

The combustion of heptane (C7H16) forms carbon dioxide and water. What is the stoichiometric coefficient for water in the balanced equation when 1 mol of heptane undergoes combustion?

Accepted Answer

A) 6 
B)    
C) 7 
D) 8 
E) 9 
A) 6 
B)    
C) 7 
D) 8 
E) 9

Question 9

A copper ore consisting of 12.5% copper(II) sulfide, when heated and reacted with oxygen gas, produces copper(II) oxide and sulfur dioxide. If the reaction has a 90.0% yield, how many grams of copper(II) oxide are produced when 1.00 kg of the copper ore is processed?

Accepted Answer

A) 93.7 g 
B) 104 g 
C) 116 g 
D) 150 g 
E) 749 g 
A) 93.7 g 
B) 104 g 
C) 116 g 
D) 150 g 
E) 749 g

Question 10

A range of organic molecules can undergo combustion. If pyridine (C5H5N) undergoes combustion through the following balanced chemical reaction, how much carbon dioxide can be produced when 3.2 g of pyridine reacts? 4C5H5N   27O2 
  H2O   20CO2    4NO

Accepted Answer

A) 0.36 g 
B) 1.2 g 
C) 1.8 g 
D) 5.8 g 
E) 8.9 g 
A) 0.36 g 
B) 1.2 g 
C) 1.8 g 
D) 5.8 g 
E) 8.9 g

Question 11

Metallic sodium was originally produced by the Deville process, where sodium carbonate and carbon black are heated to 1100S1U1P1$\circ$S1S1P0C to produce sodium (as a liquid at that temperature) and carbon monoxide gas, according to the following balanced equation.
Na2CO3(s )   2C(s )   2Na(l)   3CO(g)
If 2.3 kg of sodium carbonate is heated, what is the maximum amount of sodium that can be produced?

Accepted Answer

The answer of Metallic sodium was originally produced by the...

Question 12

Write a definition of the term molar mass.

Accepted Answer

The molar mass is th

Question 13

In which of the following reaction mixtures, where A reacts with B in the following balanced equation, is B the limiting reactant? A   2B   AB2

Accepted Answer

A)    
B)    
C)    
D)    
E)    
A)    
B)    
C)    
D)    
E)

Question 14

Which of the following cartoons depict a balanced reaction?

Accepted Answer

A)    
B)    
C)    
D)    
E)    
A)    
B)    
C)    
D)    
E)

Question 15

What is the molar mass of glucose, C6H12O6?

Accepted Answer

Question 16

Copper was the first metal to be produced from its ore because it is the easiest to smelt, that is, to refine by heating in the presence of carbon (hence the early occurrence of the Bronze Age). The ore was likely malachite (Cu2(OH)2CO3). What is the mass percent of copper in malachite?

Accepted Answer

A) 28.7% 
B) 45.2% 
C) 57.5% 
D) 40.3% 
E) 74.6% 
A) 28.7% 
B) 45.2% 
C) 57.5% 
D) 40.3% 
E) 74.6%

Question 17

Which of the following molecules have identical molecular and empirical formulas?

Accepted Answer

A) I only 
B) II only 
C) III only 
D) II, III, and IV only 
E) All have identical formulas. 
A) I only 
B) II only 
C) III only 
D) II, III, and IV only 
E) All have identical formulas.

Question 18

Chemical analysis of an organic compound found the following composition: 40.0% C, 53.5% O, and 6.7% H. If the molar mass is 180.2 g/mol, how many empirical formula units are there in the molecular formula?

Accepted Answer

A) 2 
B) 4 
C) 8 
D) 6 
E) 7 
A) 2 
B) 4 
C) 8 
D) 6 
E) 7

Question 19

Which statement A-D regarding photosynthesis is not correct? In the process of photosynthesis ________

Accepted Answer

A) light energy is converted into carbon-based fuels. 
B) oxygen is produced. 
C) atmospheric carbon dioxide is consumed. 
D) the sugar glucose is produced. 
E) A-D are all correct. 
A) light energy is converted into carbon-based fuels. 
B) oxygen is produced. 
C) atmospheric carbon dioxide is consumed. 
D) the sugar glucose is produced. 
E) A-D are all correct.

Question 20

Ammonia, NH3, is an important industrial chemical. It is produced using the Haber process from nitrogen, N2, and hydrogen, H2. How much ammonia can be produced from 28 kg of nitrogen and 2 kg of hydrogen, assuming the reaction yield is 90%?

Accepted Answer

A) 10.2 kg 
B) 11.3 kg 
C) 17.0 kg 
D) 34.0 kg 
E) 9.95 kg 
A) 10.2 kg 
B) 11.3 kg 
C) 17.0 kg 
D) 34.0 kg 
E) 9.95 kg

Exam 3: Stoichiometry: Mass, Formulas, and Reactions

What is the molar mass of sulfuric acid (H2SO4)?

The empirical formula for buckminsterfullerene is C1, and its molar mass is 720.6 g/mol. What is its molecular formula?

Caffeine has an elemental analysis of 49.48% carbon, 5.190% hydrogen, 16.47% oxygen, and 28.85% nitrogen. It has a molar mass of 194.19 g/mol. What is the molecular formula of caffeine?

How many nitrogen atoms are there in 51.0 g of (NH4)2SO4 (ammonium sulfate)?

Phosphorus trichloride reacts with water to form phosphorous acid, H3PO3, and hydrochloric acid in the following unbalanced reaction. For each mole of phosphorous acid produced by this reaction, how many moles of HCl are produced?__ PCl3 __H2O __H3PO3 + __ HCl

Identify the list below that has these chloride compounds arranged in order of increasing molar mass.

Mesitylene is a liquid hydrocarbon. If 0.115 g of this compound is burned in pure oxygen to give 0.3790 g CO2 and 0.1035 g H2O, what is the empirical formula of the compound?

The combustion of heptane (C7H16) forms carbon dioxide and water. What is the stoichiometric coefficient for water in the balanced equation when 1 mol of heptane undergoes combustion?

A copper ore consisting of 12.5% copper(II) sulfide, when heated and reacted with oxygen gas, produces copper(II) oxide and sulfur dioxide. If the reaction has a 90.0% yield, how many grams of copper(II) oxide are produced when 1.00 kg of the copper ore is processed?

A range of organic molecules can undergo combustion. If pyridine (C5H5N) undergoes combustion through the following balanced chemical reaction, how much carbon dioxide can be produced when 3.2 g of pyridine reacts? 4C5H5N 27O2 H2O 20CO2 4NO

Write a definition of the term molar mass.

In which of the following reaction mixtures, where A reacts with B in the following balanced equation, is B the limiting reactant? A 2B AB2

Which of the following cartoons depict a balanced reaction?

What is the molar mass of glucose, C6H12O6?

Copper was the first metal to be produced from its ore because it is the easiest to smelt, that is, to refine by heating in the presence of carbon (hence the early occurrence of the Bronze Age). The ore was likely malachite (Cu2(OH)2CO3). What is the mass percent of copper in malachite?

Which of the following molecules have identical molecular and empirical formulas?

Chemical analysis of an organic compound found the following composition: 40.0% C, 53.5% O, and 6.7% H. If the molar mass is 180.2 g/mol, how many empirical formula units are there in the molecular formula?

Which statement A-D regarding photosynthesis is not correct? In the process of photosynthesis ________

Ammonia, NH3, is an important industrial chemical. It is produced using the Haber process from nitrogen, N2, and hydrogen, H2. How much ammonia can be produced from 28 kg of nitrogen and 2 kg of hydrogen, assuming the reaction yield is 90%?

Matter and Energy: The Origin of the Universe

Atoms, Ions, and Molecules: Matter Starts Here

Solution Chemistry: The Hydrosphere

Thermochemistry: Energy Changes in Reactions

Properties of Gases: The Air We Breathe

A Quantum Model of Atoms: Waves and Particles

Chemical Bonds: What Makes a Gas a Greenhouse Gas

Molecular Geometry: Shape Determines Function

Intermolecular Forces: The Uniqueness of Water

Solutions: Properties and Behavior

Solids: Crystals, Alloys, and Polymers

Chemical Kinetics: Reactions in the Atmosphere

Chemical Equilibrium: How Much Product Does a Reaction Really Make

Acidbase Equilibria: Proton Transfer in Biological Systems

Additional Aqueous Equilibria: Chemistry and the Oceans

Thermodynamics: Spontaneous and Nonspontaneous Reactions and Processes

Electrochemistry: The Quest for Clean Energy

Nuclear Chemistry: Applications to Energy and Medicine

Organic and Biological Molecules: the Compounds of Life

The Main Group Elements: Life and the Periodic Table

Transition Metals: Biological and Medical Applications

Filters

What is the molar mass of sulfuric acid (H₂SO₄)?

The empirical formula for buckminsterfullerene is C₁, and its molar mass is 720.6 g/mol. What is its molecular formula?

How many nitrogen atoms are there in 51.0 g of (NH₄)₂SO₄ (ammonium sulfate)?

Phosphorus trichloride reacts with water to form phosphorous acid, H₃PO₃, and hydrochloric acid in the following unbalanced reaction. For each mole of phosphorous acid produced by this reaction, how many moles of HCl are produced? PCl₃ H₂O H₃PO₃ + HCl

Mesitylene is a liquid hydrocarbon. If 0.115 g of this compound is burned in pure oxygen to give 0.3790 g CO₂ and 0.1035 g H₂O, what is the empirical formula of the compound?

The combustion of heptane (C₇H₁₆) forms carbon dioxide and water. What is the stoichiometric coefficient for water in the balanced equation when 1 mol of heptane undergoes combustion?

A range of organic molecules can undergo combustion. If pyridine (C₅H₅N) undergoes combustion through the following balanced chemical reaction, how much carbon dioxide can be produced when 3.2 g of pyridine reacts? 4C₅H₅N 27O₂ H₂O 20CO₂ 4NO

In which of the following reaction mixtures, where A reacts with B in the following balanced equation, is B the limiting reactant? A 2B AB₂

What is the molar mass of glucose, C₆H₁₂O₆?

Copper was the first metal to be produced from its ore because it is the easiest to smelt, that is, to refine by heating in the presence of carbon (hence the early occurrence of the Bronze Age). The ore was likely malachite (Cu₂(OH)₂CO₃). What is the mass percent of copper in malachite?

Ammonia, NH₃, is an important industrial chemical. It is produced using the Haber process from nitrogen, N₂, and hydrogen, H₂. How much ammonia can be produced from 28 kg of nitrogen and 2 kg of hydrogen, assuming the reaction yield is 90%?