Question 1

Hematite is the mineral form of iron(III)oxide.Calculate the number of iron ions in 20.0 kg of pure hematite.

Accepted Answer

A) 1.51 × 1026  
B) 7.54 × 1025 
C) 3.77 × 1017 
D) 6.63 × 10-27 
E) 9.62 × 1021 
A) 1.51 × 1026  
B) 7.54 × 1025 
C) 3.77 × 1017 
D) 6.63 × 10-27 
E) 9.62 × 1021

Question 2

Which of the following is an ionic compound?

Accepted Answer

A) LiCl 
B) NO2 
C) PCl3 
D) CF4 
E) SeBr2 
A) LiCl 
B) NO2 
C) PCl3 
D) CF4 
E) SeBr2

Question 3

Identify the compound with (an)ionic bond(s).

Accepted Answer

A) SO2 
B) CO 
C) O2 
D) H2O 
E) KBr 
A) SO2 
B) CO 
C) O2 
D) H2O 
E) KBr

Question 4

Combustion analysis of 1.200 g of an unknown compound containing carbon,hydrogen,and oxygen produced 2.086 g of CO2 and 1.134 g of H2O.What is the empirical formula of the compound?

Accepted Answer

A) C2H5O 
B) C2H5O2 
C) C2H10O3 
D) C3H8O2 
A) C2H5O 
B) C2H5O2 
C) C2H10O3 
D) C3H8O2

Question 5

Determine the name for TiCO3.Remember that titanium forms several ions.

Accepted Answer

A) titanium(II)carbonate 
B) titanium carbide 
C) titanium carbonite 
D) titanium(II)carbonite 
E) titanium(I)carbonate 
A) titanium(II)carbonate 
B) titanium carbide 
C) titanium carbonite 
D) titanium(II)carbonite 
E) titanium(I)carbonate

Question 6

What is the mass of 8.50 × 1022 molecules of NH3?

Accepted Answer

A) 0.00829 g 
B) 0.417 g 
C) 2.40 g 
D) 121 g 
A) 0.00829 g 
B) 0.417 g 
C) 2.40 g 
D) 121 g

Question 7

Combustion analysis of 63.8 mg of a C,H,and O-containing compound produced 145.0 mg of CO2 and 59.38 mg of H2O.What is the empirical formula for the compound?

Accepted Answer

A) C5H2O 
B) CHO 
C) C3H6O 
D) C3H7O 
E) C6HO3 
A) C5H2O 
B) CHO 
C) C3H6O 
D) C3H7O 
E) C6HO3

Question 8

What is the mass of 0.500 mol of dichlorodifluoromethane,CCl2F2?

Accepted Answer

A) 4.14 × 10-3 g 
B) 60.5 g 
C) 121 g 
D) 242 g 
A) 4.14 × 10-3 g 
B) 60.5 g 
C) 121 g 
D) 242 g

Question 9

How many molecules of N2O4 are in 76.3 g N2O4? The molar mass of N2O4 is 92.02 g mol-1.

Accepted Answer

A) 5.54 × 1025 N2O4 molecules 
B) 7.26 × 1023 N2O4 molecules 
C) 1.38 × 1024 N2O4 molecules 
D) 4.59 × 1025 N2O4 molecules 
E) 4.99 × 1023 N2O4 molecules 
A) 5.54 × 1025 N2O4 molecules 
B) 7.26 × 1023 N2O4 molecules 
C) 1.38 × 1024 N2O4 molecules 
D) 4.59 × 1025 N2O4 molecules 
E) 4.99 × 1023 N2O4 molecules

Question 10

Which of the following is the correct chemical formula for a molecule of astatine?

Accepted Answer

A) At 
B) At- 
C) At+ 
D) At2 
A) At 
B) At- 
C) At+ 
D) At2

Question 11

What is the empirical formula of a compound that is 66.6% C,11.2% H,and 22.2% O by mass?

Accepted Answer

A) C5H10O2 
B) C8HO4 
C) C6H12O2 
D) C4H8O 
E) C4H2O 
A) C5H10O2 
B) C8HO4 
C) C6H12O2 
D) C4H8O 
E) C4H2O

Question 12

Describe the difference between a molecular formula and an empirical formula.Give an example.

Accepted Answer

A molecular formula is the exact number

Question 13

What is the correct formula for lead (II)chloride?

Accepted Answer

A) LdCl4 
B) SbCl4 
C) PbCl2 
D) PbCl4 
E) LaCl3 
A) LdCl4 
B) SbCl4 
C) PbCl2 
D) PbCl4 
E) LaCl3

Question 14

Determine the name for N2O5.

Accepted Answer

A) dinitrogen pentoxide 
B) nitrogen oxide 
C) nitrogen(IV)oxide 
D) nitrogen(II)oxide 
E) nitrogen tetroxide 
A) dinitrogen pentoxide 
B) nitrogen oxide 
C) nitrogen(IV)oxide 
D) nitrogen(II)oxide 
E) nitrogen tetroxide

Question 15

Identify the formula for barium hydroxide octahydrate.

Accepted Answer

A) Ba(OH)2∙8H2O 
B) BaOH∙8H2O 
C) B(OH)3∙8H2O 
D) 8Ba(OH)2∙H2O 
E) 8BaOH∙H2O 
A) Ba(OH)2∙8H2O 
B) BaOH∙8H2O 
C) B(OH)3∙8H2O 
D) 8Ba(OH)2∙H2O 
E) 8BaOH∙H2O

Question 16

What is the empirical formula for C4H10O2?

Accepted Answer

A) C2H5O 
B) CHO 
C) C2H4O 
D) CHO2 
E) CH2O 
A) C2H5O 
B) CHO 
C) C2H4O 
D) CHO2 
E) CH2O

Question 17

What is the charge on the Cr ions in Cr2O3?

Accepted Answer

A) 2- 
B) 1+ 
C) 2+ 
D) 3+ 
A) 2- 
B) 1+ 
C) 2+ 
D) 3+

Question 18

Which of the following has the greatest mass?

Accepted Answer

A) 3.88 × 1022 molecules of O2 
B) 1.00 g of O2 
C) 0.0312 mol of O2 
D) All of the above have the same mass. 
A) 3.88 × 1022 molecules of O2 
B) 1.00 g of O2 
C) 0.0312 mol of O2 
D) All of the above have the same mass.

Question 19

How many C2H4 molecules are contained in 45.8 mg of C2H4? The molar mass of C2H4 is 28.05 g mol-1.

Accepted Answer

A) 9.83 × 1020 C2H4 molecules 
B) 7.74 × 1026 C2H4 molecules 
C) 2.71 × 1020 C2H4 molecules 
D) 3.69 × 1023 C2H4 molecules 
E) 4.69 × 1023 C2H4 molecules 
A) 9.83 × 1020 C2H4 molecules 
B) 7.74 × 1026 C2H4 molecules 
C) 2.71 × 1020 C2H4 molecules 
D) 3.69 × 1023 C2H4 molecules 
E) 4.69 × 1023 C2H4 molecules

Question 20

Identify the formula for sodium chlorate.

Accepted Answer

A) NaClO 
B) NaClO2 
C) NaClO3 
D) NaClO4 
A) NaClO 
B) NaClO2 
C) NaClO3 
D) NaClO4

Exam 3: Molecules,compounds,and Nomenclature

Hematite is the mineral form of iron(III)oxide.Calculate the number of iron ions in 20.0 kg of pure hematite.

Which of the following is an ionic compound?

Identify the compound with (an)ionic bond(s).

Combustion analysis of 1.200 g of an unknown compound containing carbon,hydrogen,and oxygen produced 2.086 g of CO2 and 1.134 g of H2O.What is the empirical formula of the compound?

Determine the name for TiCO3.Remember that titanium forms several ions.

What is the mass of 8.50 × 1022 molecules of NH3?

Combustion analysis of 63.8 mg of a C,H,and O-containing compound produced 145.0 mg of CO2 and 59.38 mg of H2O.What is the empirical formula for the compound?

What is the mass of 0.500 mol of dichlorodifluoromethane,CCl2F2?

How many molecules of N2O4 are in 76.3 g N2O4? The molar mass of N2O4 is 92.02 g mol-1.

Which of the following is the correct chemical formula for a molecule of astatine?

What is the empirical formula of a compound that is 66.6% C,11.2% H,and 22.2% O by mass?

Describe the difference between a molecular formula and an empirical formula.Give an example.

What is the correct formula for lead (II)chloride?

Determine the name for N2O5.

Identify the formula for barium hydroxide octahydrate.

What is the empirical formula for C4H10O2?

What is the charge on the Cr ions in Cr2O3?

Which of the following has the greatest mass?

How many C2H4 molecules are contained in 45.8 mg of C2H4? The molar mass of C2H4 is 28.05 g mol-1.

Identify the formula for sodium chlorate.

Units of Measurement for Physical and Chemical Change

Atoms and Elements

Chemical Reactions and Stoichiometry

Gases

Thermochemistry

The Quantum-Mechanical Model of the Atom

Periodic Properties of the Elements

Chemical Bonding I: Lewis Theory

Chemical Bonding II: Molecular Shapes, valence Bond Theory, and Molecular Orbital Theory

Liquids, solids, and Intermolecular Forces

Solutions

Chemical Kinetics

Chemical Equilibrium

Acids and Bases

Aqueous Ionic Equilibrium

Gibbs Energy and Thermodynamics

Electrochemistry

Radioactivity and Nuclear Chemistry

Organic Chemistry I: Structures

Organic Chemistry II: Reactions

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Chemistry of the Nonmetals

Metals and Metallurgy

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Filters

Combustion analysis of 1.200 g of an unknown compound containing carbon,hydrogen,and oxygen produced 2.086 g of CO₂ and 1.134 g of H₂O.What is the empirical formula of the compound?

Determine the name for TiCO₃.Remember that titanium forms several ions.

What is the mass of 8.50 × 10²² molecules of NH₃?

Combustion analysis of 63.8 mg of a C,H,and O-containing compound produced 145.0 mg of CO₂ and 59.38 mg of H₂O.What is the empirical formula for the compound?

What is the mass of 0.500 mol of dichlorodifluoromethane,CCl₂F₂?

How many molecules of N₂O₄ are in 76.3 g N₂O₄? The molar mass of N₂O₄ is 92.02 g mol^-1.

Determine the name for N₂O₅.

What is the empirical formula for C₄H₁₀O₂?

What is the charge on the Cr ions in Cr₂O₃?

How many C₂H₄ molecules are contained in 45.8 mg of C₂H₄? The molar mass of C₂H₄ is 28.05 g mol^-1.