Question 1

Which one of the following statements about balanced equations is false? In a balanced reaction

Accepted Answer

A) atoms must be balanced on both sides of the reaction arrow. 
B) mass must be conserved. 
C) molecules must be balanced on both sides of the reaction arrow. 
D) net charge must be balanced on both sides of the reaction arrow. 
A) atoms must be balanced on both sides of the reaction arrow. 
B) mass must be conserved. 
C) molecules must be balanced on both sides of the reaction arrow. 
D) net charge must be balanced on both sides of the reaction arrow.

Question 2

Tablets of ascorbic acid,or Vitamin C,C6H8O6,are taken as a dietary supplement.If a typical tablet contains 500 mg,how many atoms of carbon (C)are in a tablet?

Accepted Answer

1.026 × 10

Question 3

What is the mass of 0.0500 mol of dichlorodifluoromethane,CF2Cl2?

Accepted Answer

A) 4.14 × 10-4 g 
B) 6.05 g 
C) 12.1 g 
D) 24.2 g 
A) 4.14 × 10-4 g 
B) 6.05 g 
C) 12.1 g 
D) 24.2 g

Question 4

What mass of carbon monoxide,CO,contains the same number of molecules as 3.00 g of trichlorofluoromethane,CCl3F?

Accepted Answer

A) 3.00 g 
B) 0.612 g 
C) 1.63 g 
D) 9.33 g 
A) 3.00 g 
B) 0.612 g 
C) 1.63 g 
D) 9.33 g

Question 5

What is the empirical formula of a substance that contains 2.64 g of C,0.444 g of H,and 3.52 g of O?

Accepted Answer

A) CH2O  
B) C2H4O2 
C) C2H4O3 
D) C3H4O4 
A) CH2O  
B) C2H4O2 
C) C2H4O3 
D) C3H4O4

Question 6

How many grams of calcium chloride are needed to produce 5.00 g of potassium chloride? CaCl2(aq)+ K2CO3(aq)→ 2 KCl(aq)+ CaCO3(aq)

Accepted Answer

A) 0.269 g 
B) 3.72 g 
C) 7.44 g 
D) 14.9 g 
A) 0.269 g 
B) 3.72 g 
C) 7.44 g 
D) 14.9 g

Question 7

What is the molar mass of aspirin if 5.19 × 1016 molecules of aspirin weigh 15.53 μg?

Accepted Answer

A) 180 g/mol 
B) 80.6 g/mol 
C) 133.8 g/mol 
D) 200 g/mol 
A) 180 g/mol 
B) 80.6 g/mol 
C) 133.8 g/mol 
D) 200 g/mol

Question 8

When silver nitrate reacts with barium chloride,silver chloride and barium nitrate are formed.How many grams of silver chloride are formed when 10.8 g of silver nitrate reacts with 15.0 g of barium chloride?

Accepted Answer

A) 9.11 g 
B) 9.40 g 
C) 12.9 g 
D) 18.8 g 
A) 9.11 g 
B) 9.40 g 
C) 12.9 g 
D) 18.8 g

Question 9

When silver nitrate reacts with barium chloride,silver chloride and barium nitrate are formed.How many grams of silver chloride are formed when 8.0 g of silver nitrate reacts with 15.0 g of barium chloride?

Accepted Answer

A) 6.752 g 
B) 9.40 g 
C) 11.9 g 
D) 18.8 g 
A) 6.752 g 
B) 9.40 g 
C) 11.9 g 
D) 18.8 g

Question 10

Which statement about elemental analysis by combustion is not correct?

Accepted Answer

A) Carbon is determined from the amount of CO2 formed. 
B) Hydrogen is determined from the amount of H2O formed. 
C) Oxygen is determined from the amount of H2O formed. 
D) Only carbon and hydrogen can be determined directly from CO2 and H2O. 
A) Carbon is determined from the amount of CO2 formed. 
B) Hydrogen is determined from the amount of H2O formed. 
C) Oxygen is determined from the amount of H2O formed. 
D) Only carbon and hydrogen can be determined directly from CO2 and H2O.

Question 11

What is the number of moles of 5.00 × 1022 molecules of NaBr?

Accepted Answer

A) 0.037 moles 
B) 1.0 moles 
C) 0.083 moles 
D) 1.2046 moles 
A) 0.037 moles 
B) 1.0 moles 
C) 0.083 moles 
D) 1.2046 moles

Question 12

What is the empirical formula for ethyl fluoride if the compound contains 49.97% carbon,10.51% hydrogen,and 39.52% fluorine by mass?

Accepted Answer

A) C2H5F 
B) C4H10F2 
C) C4H10F4 
D) C25F2 
A) C2H5F 
B) C4H10F2 
C) C4H10F4 
D) C25F2

Question 13

If the percent yield for the following reaction is 75.0%,and 35.0 g of NO2 are consumed in the reaction,how many grams of nitric acid,HNO3(aq)are produced? 3 NO2(g)+ H2O(l)→ 2 HNO3(aq)+ NO(g)

Accepted Answer

A) 24.0 g 
B) 31.9 g 
C) 42.6 g 
D) 53.9 g 
A) 24.0 g 
B) 31.9 g 
C) 42.6 g 
D) 53.9 g

Question 14

The following diagram represents the reaction of A2 (unshaded spheres)with B2 (shaded spheres).How many moles of product can be produced from the reaction of 1.0 mol of A2 and 1.0 mol of B2?

Accepted Answer

A) 0.5 mol of product 
B) 1.0 mol of product 
C) 2.0 mol of product 
D) 4.0 mol of product 
A) 0.5 mol of product 
B) 1.0 mol of product 
C) 2.0 mol of product 
D) 4.0 mol of product

Question 15

-Diethyl ether has the molecular formula C4H10O.Which ball and stick model shown above represents diethyl ether? [gray spheres = C,black spheres = O,unshaded spheres = H]

Accepted Answer

A) model a) 
B) model b) 
C) model c) 
D) model d) 
A) model a) 
B) model b) 
C) model c) 
D) model d)

Question 16

Which of the following statements is false concerning the formula of a compound?

Accepted Answer

A) The empirical formula is the simplest whole numbered ratio of atoms in a compound. 
B) The molecular formula is the true ratio of atoms in a compound. 
C) The molecular formula and empirical formula can be identical. 
D) The number of atoms in a molecular formula is always greater than the number of atoms in an empirical formula. 
A) The empirical formula is the simplest whole numbered ratio of atoms in a compound. 
B) The molecular formula is the true ratio of atoms in a compound. 
C) The molecular formula and empirical formula can be identical. 
D) The number of atoms in a molecular formula is always greater than the number of atoms in an empirical formula.

Question 17

The fundamental SI unit for measuring matter is the ________.

Accepted Answer

The answer of The fundamental SI unit for measuring matter...

Question 18

The density of ethanol,C2H5OH,is 0.789 g/mL.How many milliliters of ethanol are needed to produce 5.00 g of CO2 according to the following chemical equation? 
C2H5OH(l)+ 3 O2(g)→ 2 CO2(g)+ 3 H2O(l)

Accepted Answer

A) 2.06 mL 
B) 3.32 mL 
C) 6.60 mL 
D) 13.3 mL 
A) 2.06 mL 
B) 3.32 mL 
C) 6.60 mL 
D) 13.3 mL

Question 19

Which represents one formula unit?

Accepted Answer

A) One Cu 
B) One F2 
C) One NaH 
D) All of these 
A) One Cu 
B) One F2 
C) One NaH 
D) All of these

Question 20

Dinitrogen monoxide gas decomposes to form nitrogen gas and oxygen gas.How many grams of nitrogen are formed when 30.00 g of dinitrogen monoxide decomposes?

Accepted Answer

A) 9.545 g 
B) 19.09 g 
C) 30.00 g 
D) 60.00 g 
A) 9.545 g 
B) 19.09 g 
C) 30.00 g 
D) 60.00 g

Exam 3: Mass Relationships in Chemical Reactions

Which one of the following statements about balanced equations is false? In a balanced reaction

Tablets of ascorbic acid,or Vitamin C,C6H8O6,are taken as a dietary supplement.If a typical tablet contains 500 mg,how many atoms of carbon (C)are in a tablet?

What is the mass of 0.0500 mol of dichlorodifluoromethane,CF2Cl2?

What mass of carbon monoxide,CO,contains the same number of molecules as 3.00 g of trichlorofluoromethane,CCl3F?

What is the empirical formula of a substance that contains 2.64 g of C,0.444 g of H,and 3.52 g of O?

How many grams of calcium chloride are needed to produce 5.00 g of potassium chloride? CaCl2(aq)+ K2CO3(aq)→ 2 KCl(aq)+ CaCO3(aq)

What is the molar mass of aspirin if 5.19 × 1016 molecules of aspirin weigh 15.53 μg?

When silver nitrate reacts with barium chloride,silver chloride and barium nitrate are formed.How many grams of silver chloride are formed when 10.8 g of silver nitrate reacts with 15.0 g of barium chloride?

When silver nitrate reacts with barium chloride,silver chloride and barium nitrate are formed.How many grams of silver chloride are formed when 8.0 g of silver nitrate reacts with 15.0 g of barium chloride?

Which statement about elemental analysis by combustion is not correct?

What is the number of moles of 5.00 × 1022 molecules of NaBr?

What is the empirical formula for ethyl fluoride if the compound contains 49.97% carbon,10.51% hydrogen,and 39.52% fluorine by mass?

If the percent yield for the following reaction is 75.0%,and 35.0 g of NO2 are consumed in the reaction,how many grams of nitric acid,HNO3(aq)are produced? 3 NO2(g)+ H2O(l)→ 2 HNO3(aq)+ NO(g)

The following diagram represents the reaction of A2 (unshaded spheres)with B2 (shaded spheres).How many moles of product can be produced from the reaction of 1.0 mol of A2 and 1.0 mol of B2?

-Diethyl ether has the molecular formula C4H10O.Which ball and stick model shown above represents diethyl ether? [gray spheres = C,black spheres = O,unshaded spheres = H]

Which of the following statements is false concerning the formula of a compound?

The fundamental SI unit for measuring matter is the ________.

The density of ethanol,C2H5OH,is 0.789 g/mL.How many milliliters of ethanol are needed to produce 5.00 g of CO2 according to the following chemical equation? C2H5OH(l)+ 3 O2(g)→ 2 CO2(g)+ 3 H2O(l)

Which represents one formula unit?

Dinitrogen monoxide gas decomposes to form nitrogen gas and oxygen gas.How many grams of nitrogen are formed when 30.00 g of dinitrogen monoxide decomposes?

Chemical Tools: Experimentation and Measurement

Atoms, molecules, and Ions

Reactions in Aqueous Solutions

Periodicity and the Electronic Structure of Atoms

Ionic Compounds: Periodic Trends and Bonding

Covalent Bonding and Electron-Dot Structures

Covalent Compounds: Bonding Theories and Molecular Structure

Thermochemistry: Chemical Energy

Gases: Their Properties and Behavior

Liquids, solids, and Phase Changes

Solutions and Their Properties

Chemical Kinetics

Chemical Equilibrium

Aqueous Equilibria: Acids and Bases

Applications of Aqueous Equilibria

Thermodynamics: Entropy, free Energy, and Equilibrium

Electrochemistry

Nuclear Chemistry

Transition Elements and Coordination Chemistry

Metals and Solid-State Materials

The Main-Group Elements

Connections to Organic and Biological Chemistry

Filters

Tablets of ascorbic acid,or Vitamin C,C₆H₈O₆,are taken as a dietary supplement.If a typical tablet contains 500 mg,how many atoms of carbon (C)are in a tablet?

What is the mass of 0.0500 mol of dichlorodifluoromethane,CF₂Cl₂?

What mass of carbon monoxide,CO,contains the same number of molecules as 3.00 g of trichlorofluoromethane,CCl₃F?

How many grams of calcium chloride are needed to produce 5.00 g of potassium chloride? CaCl₂(aq)+ K₂CO₃(aq)→ 2 KCl(aq)+ CaCO₃(aq)

What is the molar mass of aspirin if 5.19 × 10¹⁶ molecules of aspirin weigh 15.53 μg?

What is the number of moles of 5.00 × 10²² molecules of NaBr?

If the percent yield for the following reaction is 75.0%,and 35.0 g of NO₂ are consumed in the reaction,how many grams of nitric acid,HNO₃(aq)are produced? 3 NO₂(g)+ H₂O(l)→ 2 HNO₃(aq)+ NO(g)

The following diagram represents the reaction of A₂ (unshaded spheres)with B₂ (shaded spheres).How many moles of product can be produced from the reaction of 1.0 mol of A₂ and 1.0 mol of B₂?

-Diethyl ether has the molecular formula C₄H₁₀O.Which ball and stick model shown above represents diethyl ether? [gray spheres = C,black spheres = O,unshaded spheres = H]

The density of ethanol,C₂H₅OH,is 0.789 g/mL.How many milliliters of ethanol are needed to produce 5.00 g of CO₂ according to the following chemical equation? C₂H₅OH(l)+ 3 O₂(g)→ 2 CO₂(g)+ 3 H₂O(l)