Question 1

Balance the following equation: C8H18O3(l) + O2(g) $\rightarrow$ H2O(g) + CO2(g)

Accepted Answer

A)  C8H18O3(l) + 8O2(g) $\rightarrow$ 9H2O(g) + 8CO2(g) 
B)  C8H18O3(l) + 11O2(g) $\rightarrow$ 9H2O(g) + 8CO2(g) 
C)  2C8H18O3(l) + 22O2(g) $\rightarrow$ 9H2O(g) + 16CO2(g) 
D)  C8H18O3(l) + 13O2(g) $\rightarrow$18H2O(g) + 8CO2(g) 
E)  2C8H18O3(l) + 17O2(g) $\rightarrow$ 18H2O(g) + 16CO2(g) 
A)  C8H18O3(l) + 8O2(g) $\rightarrow$ 9H2O(g) + 8CO2(g) 
B)  C8H18O3(l) + 11O2(g) $\rightarrow$ 9H2O(g) + 8CO2(g) 
C)  2C8H18O3(l) + 22O2(g) $\rightarrow$ 9H2O(g) + 16CO2(g) 
D)  C8H18O3(l) + 13O2(g) $\rightarrow$18H2O(g) + 8CO2(g) 
E)  2C8H18O3(l) + 17O2(g) $\rightarrow$ 18H2O(g) + 16CO2(g)

Question 2

Calculate the molar mass of Ca(BO2)2·6H2O.

Accepted Answer

A)  273.87 g/mol 
B)  233.79 g/mol 
C)  183.79 g/mol 
D)  174.89 g/mol 
E)  143.71 g/mol 
A)  273.87 g/mol 
B)  233.79 g/mol 
C)  183.79 g/mol 
D)  174.89 g/mol 
E)  143.71 g/mol

Question 3

Aluminum metal reacts with chlorine gas to form solid aluminum trichloride, AlCl3. What mass of chlorine gas is needed to react completely with 163 g of aluminum?

Accepted Answer

A)  214 g 
B)  245 g 
C)  321 g 
D)  489 g 
E)  643 g 
A)  214 g 
B)  245 g 
C)  321 g 
D)  489 g 
E)  643 g

Question 4

The correct method for preparing one liter of a 1.0 M solution of X is to dissolve exactly one mole of X in exactly one liter of water.

Accepted Answer

A) True 
 B)False

Question 5

Calculate the number of moles in 17.8 g of the antacid magnesium hydroxide, Mg(OH)2.

Accepted Answer

A)  3.28 mol 
B)  2.32 mol 
C)  0.431 mol 
D)  0.305 mol 
E)  0.200 mol 
A)  3.28 mol 
B)  2.32 mol 
C)  0.431 mol 
D)  0.305 mol 
E)  0.200 mol

Question 6

How many protons are there in a molecule of adrenaline (C9H13NO3), a neurotransmitter and hormone?

Accepted Answer

A)  22 
B)  26 
C)  43 
D)  98 
E)  183 
A)  22 
B)  26 
C)  43 
D)  98 
E)  183

Question 7

Copper(II) sulfide, CuS, is used in the development of aniline black dye in textile printing. What is the maximum mass of CuS which can be formed when 38.0 mL of 0.500 M CuCl2 are mixed with 42.0 mL of 0.600 M (NH4)2S? Aqueous ammonium chloride is the other product.

Accepted Answer

A)  2.41 g 
B)  1.82 g 
C)  1.21 g 
D)  0.909 g 
E)  0.044 g 
A)  2.41 g 
B)  1.82 g 
C)  1.21 g 
D)  0.909 g 
E)  0.044 g

Question 8

Balance the following equation for the combustion of benzene: C6H6(l) + O2(g)$\rightarrow$H2O(g) + CO2(g)

Accepted Answer

A)  C6H6(l) + 9O2(g) $\rightarrow$ 3H2O(g) + 6CO2(g) 
B)  C6H6(l) + 9O2(g) $\rightarrow$6H2O(g) + 6CO2(g) 
C)  2C6H6(l) + 15O2(g) $\rightarrow$6H2O(g) + 12CO2(g) 
D)  C6H6(l) + 15O2(g) $\rightarrow$3H2O(g) + 6CO2(g) 
E)  2C6H6(l) + 9O2(g) $\rightarrow$6H2O(g) + 12CO2(g) 
A)  C6H6(l) + 9O2(g) $\rightarrow$ 3H2O(g) + 6CO2(g) 
B)  C6H6(l) + 9O2(g) $\rightarrow$6H2O(g) + 6CO2(g) 
C)  2C6H6(l) + 15O2(g) $\rightarrow$6H2O(g) + 12CO2(g) 
D)  C6H6(l) + 15O2(g) $\rightarrow$3H2O(g) + 6CO2(g) 
E)  2C6H6(l) + 9O2(g) $\rightarrow$6H2O(g) + 12CO2(g)

Question 9

Constitutional (structural) isomers have the same molecular formula but different structural formulas.

Accepted Answer

A) True 
 B)False

Question 10

Consider the balanced equation: Al2S3(s) + 6H2O(l) $\rightarrow$2Al(OH)3(s) + 3H2S(g)
If 15.0 g of aluminum sulfide and 10.0 g of water are allowed to react as above, and assuming a complete reaction
A) by calculation, find out which is the limiting reagent.
B) calculate the maximum mass of H2S which can be formed from these reagents.
C) calculate the mass of excess reagent remaining after the reaction is complete.

Accepted Answer

a. Water is the limi

Question 11

Terephthalic acid, used in the production of polyester fibers and films, is composed of carbon, hydrogen, and oxygen. When 0.6943 g of terephthalic acid was subjected to combustion analysis it produced 1.471 g CO2 and 0.226 g H2O. What is its empirical formula?

Accepted Answer

A)  C2H3O4 
B)  C3H4O2 
C)  C4H3O2 
D)  C5H12O4 
E)  C2H2O 
A)  C2H3O4 
B)  C3H4O2 
C)  C4H3O2 
D)  C5H12O4 
E)  C2H2O

Question 12

Lithium hydroxide is used in alkaline batteries. Calculate the molarity of a solution prepared by dissolving 1.495 moles of LiOH in enough water to give a final volume of 750. mL.

Accepted Answer

A)  1.99 M 
B)  1.50 M 
C)  1.12 M 
D)  0.502 M 
E)  0.00199 M 
A)  1.99 M 
B)  1.50 M 
C)  1.12 M 
D)  0.502 M 
E)  0.00199 M

Question 13

Sodium bromate is used in a mixture which dissolves gold from its ores. Calculate the mass in grams of 4.68 mol of sodium bromate.

Accepted Answer

A)  706 g 
B)  482 g 
C)  383 g 
D)  32.2 g 
E)  0.0310 g 
A)  706 g 
B)  482 g 
C)  383 g 
D)  32.2 g 
E)  0.0310 g

Question 14

Balance the following equation: B2O3(s) + HF(l) $\rightarrow$BF3(g) + H2O(l)

Accepted Answer

A)  B2O3(s) + 6HF(l) $\rightarrow$ 2BF3(g) + 3H2O(l) 
B)  B2O3(s) + H6F6(l) $\rightarrow$B2F6(g) + H6O3(l) 
C)  B2O3(s) + 2HF(l) $\rightarrow$ 2BF3(g) + H2O(l) 
D)  B2O3(s) + 3HF(l) $\rightarrow$ 2BF3(g) + 3H2O(l) 
E)  B2O3(s) + 6HF(l) $\rightarrow$ 2BF3(g) + 6H2O(l) 
A)  B2O3(s) + 6HF(l) $\rightarrow$ 2BF3(g) + 3H2O(l) 
B)  B2O3(s) + H6F6(l) $\rightarrow$B2F6(g) + H6O3(l) 
C)  B2O3(s) + 2HF(l) $\rightarrow$ 2BF3(g) + H2O(l) 
D)  B2O3(s) + 3HF(l) $\rightarrow$ 2BF3(g) + 3H2O(l) 
E)  B2O3(s) + 6HF(l) $\rightarrow$ 2BF3(g) + 6H2O(l)

Question 15

Aluminum oxide (used as an adsorbent or a catalyst for organic reactions) forms when aluminum reacts with oxygen. 
4Al(s) + 3O2(g) $\rightarrow$2Al2O3(s)
A mixture of 82.49 g of aluminum (? = 26.98 g/mol) and 117.65 g of oxygen (? = 32.00 g/mol) is allowed to react. What mass of aluminum oxide (? = 101.96 g/mol) can be formed?

Accepted Answer

A)  155.8 g 
B)  200.2 g 
C)  249.9 g 
D)  311.7 g 
E)  374.9 g 
A)  155.8 g 
B)  200.2 g 
C)  249.9 g 
D)  311.7 g 
E)  374.9 g

Question 16

Calculate the number of oxygen atoms in 29.34 g of sodium sulfate, Na2SO4.

Accepted Answer

A)  1.244 * 1023 O atoms 
B)  4.976 * 1023 O atoms 
C)  2.409 *1024 O atoms 
D)  2.915 * 1024 O atoms 
E)  1.166 * 1025 O atoms 
A)  1.244 * 1023 O atoms 
B)  4.976 * 1023 O atoms 
C)  2.409 *1024 O atoms 
D)  2.915 * 1024 O atoms 
E)  1.166 * 1025 O atoms

Question 17

How many mL of concentrated nitric acid (HNO3, 16.0 M) should be diluted with water in order to make 2.00 L of 2.00 M solution?

Accepted Answer

A)  32.0 mL 
B)  62.5 mL 
C)  125 mL 
D)  250. mL 
E)  500. mL 
A)  32.0 mL 
B)  62.5 mL 
C)  125 mL 
D)  250. mL 
E)  500. mL

Question 18

Constitutional (structural) isomers have the same empirical formula but different molecular formulas.

Accepted Answer

A) True 
 B)False

Question 19

Phosphine, an extremely poisonous and highly reactive gas, will react with oxygen to form tetraphosphorus decaoxide and water. 
PH3(g) + O2(g) $\rightarrow$P4O10(s) + H2O(g) [unbalanced]
Calculate the mass of P4O10(s) formed when 225 g of PH3 reacts with excess oxygen.

Accepted Answer

A)  1880 g 
B)  940. g 
C)  900. g 
D)  470 g 
E)  56.3 g 
A)  1880 g 
B)  940. g 
C)  900. g 
D)  470 g 
E)  56.3 g

Question 20

Sodium hydroxide, also known as caustic soda, is used to neutralize acids and to treat cellulose in making of cellophane. Calculate the number of moles of solute in 1.875 L of 1.356 M NaOH solution.

Accepted Answer

A)  2.543 mol 
B)  1.383 mol 
C)  0.7232 mol 
D)  0.3932 mol 
E)  0.001383 mol 
A)  2.543 mol 
B)  1.383 mol 
C)  0.7232 mol 
D)  0.3932 mol 
E)  0.001383 mol

Exam 3: Stoichiometry of Formulas and Equations

Balance the following equation: C8H18O3(l) + O2(g) →\rightarrow→ H2O(g) + CO2(g)

Calculate the molar mass of Ca(BO2)2·6H2O.

Aluminum metal reacts with chlorine gas to form solid aluminum trichloride, AlCl3. What mass of chlorine gas is needed to react completely with 163 g of aluminum?

The correct method for preparing one liter of a 1.0 M solution of X is to dissolve exactly one mole of X in exactly one liter of water.

Calculate the number of moles in 17.8 g of the antacid magnesium hydroxide, Mg(OH)2.

How many protons are there in a molecule of adrenaline (C9H13NO3), a neurotransmitter and hormone?

Copper(II) sulfide, CuS, is used in the development of aniline black dye in textile printing. What is the maximum mass of CuS which can be formed when 38.0 mL of 0.500 M CuCl2 are mixed with 42.0 mL of 0.600 M (NH4)2S? Aqueous ammonium chloride is the other product.

Balance the following equation for the combustion of benzene: C6H6(l) + O2(g) →\rightarrow→ H2O(g) + CO2(g)

Constitutional (structural) isomers have the same molecular formula but different structural formulas.

Terephthalic acid, used in the production of polyester fibers and films, is composed of carbon, hydrogen, and oxygen. When 0.6943 g of terephthalic acid was subjected to combustion analysis it produced 1.471 g CO2 and 0.226 g H2O. What is its empirical formula?

Lithium hydroxide is used in alkaline batteries. Calculate the molarity of a solution prepared by dissolving 1.495 moles of LiOH in enough water to give a final volume of 750. mL.

Sodium bromate is used in a mixture which dissolves gold from its ores. Calculate the mass in grams of 4.68 mol of sodium bromate.

Balance the following equation: B2O3(s) + HF(l) →\rightarrow→ BF3(g) + H2O(l)

Calculate the number of oxygen atoms in 29.34 g of sodium sulfate, Na2SO4.

How many mL of concentrated nitric acid (HNO3, 16.0 M) should be diluted with water in order to make 2.00 L of 2.00 M solution?

Constitutional (structural) isomers have the same empirical formula but different molecular formulas.

Phosphine, an extremely poisonous and highly reactive gas, will react with oxygen to form tetraphosphorus decaoxide and water. PH3(g) + O2(g) →\rightarrow→ P4O10(s) + H2O(g) [unbalanced] Calculate the mass of P4O10(s) formed when 225 g of PH3 reacts with excess oxygen.

Sodium hydroxide, also known as caustic soda, is used to neutralize acids and to treat cellulose in making of cellophane. Calculate the number of moles of solute in 1.875 L of 1.356 M NaOH solution.

Keys to the Study of Chemistry

The Components of Matter

Three Major Classes of Chemical Reactions

Gases and the Kinetic-Molecular Theory

Thermochemistry: Energy Flow and Chemical Change

Quantum Theory and Atomic Structure

Electron Configuration and Chemical Periodicity

Models of Chemical Bonding

The Shapes of Molecules

Theories of Covalent Bonding

Intermolecular Forces: Liquids, Solids, and Phase Changes

The Properties of Mixtures: Solutions and Colloids

Periodic Patterns in the Main-Group Elements

Organic Compounds and the Atomic Properties of Carbon

Kinetics: Rates and Mechanisms of Chemical Reactions

Equilibrium: the Extent of Chemical Reactions

Acid-Base Equilibria

Ionic Equilibria in Aqueous Systems

Thermodynamics: Entropy, Free Energy, and the Direction of Chemical Reactions

Electrochemistry: Chemical Change and Electrical Work

The Elements in Nature and Industry

The Transition Elements and Their Coordination Compounds

Nuclear Reactions and Their Applications

Filters

Balance the following equation: C₈H₁₈O₃(l) + O₂(g) $\rightarrow$ H₂O(g) + CO₂(g)

Calculate the molar mass of Ca(BO₂)₂·6H₂O.

Aluminum metal reacts with chlorine gas to form solid aluminum trichloride, AlCl₃. What mass of chlorine gas is needed to react completely with 163 g of aluminum?

Calculate the number of moles in 17.8 g of the antacid magnesium hydroxide, Mg(OH)₂.

How many protons are there in a molecule of adrenaline (C₉H₁₃NO₃), a neurotransmitter and hormone?

Copper(II) sulfide, CuS, is used in the development of aniline black dye in textile printing. What is the maximum mass of CuS which can be formed when 38.0 mL of 0.500 M CuCl₂ are mixed with 42.0 mL of 0.600 M (NH₄)₂S? Aqueous ammonium chloride is the other product.

Balance the following equation for the combustion of benzene: C₆H₆(l) + O₂(g) $\rightarrow$ H₂O(g) + CO₂(g)

Terephthalic acid, used in the production of polyester fibers and films, is composed of carbon, hydrogen, and oxygen. When 0.6943 g of terephthalic acid was subjected to combustion analysis it produced 1.471 g CO₂ and 0.226 g H₂O. What is its empirical formula?

Balance the following equation: B₂O₃(s) + HF(l) $\rightarrow$ BF₃(g) + H₂O(l)

Calculate the number of oxygen atoms in 29.34 g of sodium sulfate, Na₂SO₄.

How many mL of concentrated nitric acid (HNO₃, 16.0 M) should be diluted with water in order to make 2.00 L of 2.00 M solution?

Phosphine, an extremely poisonous and highly reactive gas, will react with oxygen to form tetraphosphorus decaoxide and water. PH₃(g) + O₂(g) $\rightarrow$ P₄O₁₀(s) + H₂O(g) [unbalanced] Calculate the mass of P₄O₁₀(s) formed when 225 g of PH₃ reacts with excess oxygen.