Question 1

Hydroxylamine nitrate contains 29.17 mass % N, 4.20 mass % H, and 66.63 mass O. If its molar mass is between 94 and 98 g/mol, what is its molecular formula?

Accepted Answer

A)  NH2O5 
B)  N2H4O4 
C)  N3H3O3 
D)  N4H8O2 
E)  N2H2O4

Question 2

Aluminum sulfate, Al2(SO4)3, is used in tanning leather, purifying water, and manufacture of antiperspirants. Calculate its molar mass.

Accepted Answer

A)  450.06 g/mol 
B)  342.15 g/mol 
C)  315.15 g/mol 
D)  278.02 g/mol 
E)  74.98 g/mol

Question 3

An important reaction sequence in the industrial production of nitric acid is the following: N2(g)  + 3H2(g) F1F1F1S1F1F1F10 2NH3(g)
4NH3(g) + 5O2(g) F1F1F1S1F1F1F10 4NO(g) + 6H2O(l)
Starting from 20.0 mol of nitrogen gas in the first reaction, how many moles of oxygen gas are required in the second one?

Accepted Answer

A)  12.5 mol O2 
B)  20.0 mol O2 
C)  25.0 mol O2 
D)  50.0 mol O2 
E) 100. mol O2

Question 4

Ammonia will react with fluorine to produce dinitrogen tetrafluoride and hydrogen fluoride (used in production of aluminum, in uranium processing, and in frosting of light bulbs). 2NH3(g) + 5F2(g) F1F1F1S1F1F1F10 N2F4(g) + 6HF(g)
How many moles of NH3 are needed to react completely with 13.6 mol of F2?

Accepted Answer

A)  34.0 mol 
B)  27.2 mol 
C)  6.80 mol 
D)  5.44 mol 
E)  2.27 mol

Question 5

The number of hydrogen atoms in 0.050 mol of C3H8O3 is

Accepted Answer

A)  3.0 × 1022 H atoms. 
B)  1.2 × 1023 H atoms. 
C)  2.4 × 1023 H atoms. 
D)  4.8 × 1023 H atoms. 
E)  none of the above.

Question 6

Propane, C₃H₈, is commonly provided as a bottled gas for use as a fuel. In 0.200 mol of propane a. what is the mass of propane? b. what mass of carbon is present? c. how many molecules of C₃H₈ are present? d. how many hydrogen atoms are present?

Accepted Answer

The answer of Propane, C₃H₈, is commonly provided as a...

Question 7

Tetraphosphorus hexaoxide (  = 219.9 g/mol) is formed by the reaction of phosphorus with oxygen gas. P4(s) + 3O2(g) F1F1F1S1F1F1F10 P4O6(s)
If a mixture of 75.3 g of phosphorus and 38.7 g of oxygen produce 43.3 g of P4O6, what is the percent yield for the reaction?

Accepted Answer

A)  57.5% 
B)  48.8% 
C)  38.0% 
D)  32.4% 
E)  16.3%

Question 8

Balance the following equation: 
Ca3(PO4)2(s) + SiO2(s) + C(s) F1F1F1S1F1F1F10 CaSiO3(s) + CO(g) + P4(s)

Accepted Answer

A)  Ca3(PO4)2(s) + 3SiO2(s) + 8C(s) F1F1F1S1F1F1F10 3CaSiO3(s) + 8CO(g) + P4(s) 
B)  Ca3(PO4)2(s) + 3SiO2(s) + 14C(s) F1F1F1S1F1F1F10 3CaSiO3(s) + 14CO(g) + P4(s) 
C)  Ca3(PO4)2(s) + 3SiO2(s) + 8C(s) F1F1F1S1F1F1F10 3CaSiO3(s) + 8CO(g) + 2P4(s) 
D)  2Ca3(PO4)2(s) + 6SiO2(s) + 10C(s) F1F1F1S1F1F1F10 6CaSiO3(s) + 10CO(g) + P4(s) 
E)  2Ca3(PO4)2(s) + 6SiO2(s) + 10C(s) F1F1F1S1F1F1F10 6CaSiO3(s) + 10CO(g) + 4P4(s)

Question 9

Sulfur trioxide can react with atmospheric water vapor to form sulfuric acid that falls as acid rain. Calculate the mass in grams of 3.65 × 1020 molecules of SO3.

Accepted Answer

A)  6.06 × 10-4 g 
B)  2.91 × 10-2 g 
C)  4.85 × 10-2 g 
D)  20.6 g 
E)  1650 g

Question 10

In the combustion analysis of 0.1127 g of glucose (C6H12O6), what mass, in grams, of CO2 would be produced?

Accepted Answer

A)  0.0451 g 
B)  0.0825 g 
C)  0.1652 g 
D)  0.4132 g 
E)  1.466 g

Question 11

How many atoms are in a drop of mercury that has a diameter of 1.0 mm? (Volume of a sphere is 4F1F1F1S1F1F1F10r3/3; density of mercury = 13.6 g/cm3)

Accepted Answer

A)  2.1 × 1019 
B)  1.7 × 1020 
C)  2.1 × 1022 
D)  1.7 × 1023 
E)  none of the above

Question 12

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. If its molar mass is between 158 and 167 g/mol, what is its molecular formula?

Accepted Answer

A)  C4H6O7 
B)  C6H8O5 
C)  C7H12O4 
D)  C4H3O2 
E)  C8H6O4

Question 13

Balance the equation B₂O₃(s) + NaOH(aq) F1F1F1S1F1F1F10 Na₃BO₃(aq) + H₂O(l)

Accepted Answer

The answer of Balance the equation B₂O₃(s) + NaOH(aq) F1F1F1S1F1F1F10 Na₃BO₃(aq)...

Question 14

Aluminum oxide, Al2O3, is used as a filler for paints and varnishes as well as in the manufacture of electrical insulators. Calculate the number of moles in 47.51 g of Al2O3.

Accepted Answer

A)  2.377 mol 
B)  2.146 mol 
C)  1.105 mol 
D)  0.4660 mol 
E)  0.4207 mol

Question 15

Analysis of a white solid produced in a reaction between chlorine and phosphorus showed that it contained 77.44% chlorine and 22.56% phosphorus. What is its empirical formula?

Accepted Answer

The answer of Analysis of a white solid produced in...

Question 16

Magnesium reacts with iron(III) chloride to form magnesium chloride (which can be used in fireproofing wood and in disinfectants) and iron. 3Mg(s) + 2FeCl3(s) F1F1F1S1F1F1F10 3MgCl2(s) + 2Fe(s)
A mixture of 41.0 g of magnesium (  = 24.31 g/mol) and 175 g of iron(III) chloride (  = 162.2 g/mol) is allowed to react. What mass of magnesium chloride = 95.21 g/mol) is formed?

Accepted Answer

A)  68.5 g MgCl2 
B)  77.0 g MgCl2 
C)  71.4 g MgCl2 
D)  107 g MgCl2 
E)  154 g MgCl2

Question 17

Balance the following equation for partial oxidation of ammonia, an important reaction in the production of nitric acid: NH₃(g) + O₂(g) F1F1F1S1F1F1F10 NO(g) + H₂O(l)

Accepted Answer

The answer of Balance the following equation for partial oxidation...

Question 18

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

Question 19

Lead (II) nitrate is a poisonous substance which has been used in the manufacture of special explosives and as a sensitizer in photography. Calculate the mass of lead in 139 g of Pb(NO3)2.

Accepted Answer

A)  107 g 
B)  90.8 g 
C)  87.0 g 
D)  83.4 g 
E)  62.6 g

Question 20

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

Accepted Answer

A) True 
 B)False

Exam 3: Stoichiometry of Formulas and Equations

Hydroxylamine nitrate contains 29.17 mass % N, 4.20 mass % H, and 66.63 mass O. If its molar mass is between 94 and 98 g/mol, what is its molecular formula?

Aluminum sulfate, Al₂(SO₄) ₃, is used in tanning leather, purifying water, and manufacture of antiperspirants. Calculate its molar mass.

An important reaction sequence in the industrial production of nitric acid is the following: N₂(g) + 3H₂(g)  2NH₃(g) 4NH₃(g) + 5O₂(g)  4NO(g) + 6H₂O(l) Starting from 20.0 mol of nitrogen gas in the first reaction, how many moles of oxygen gas are required in the second one?

The number of hydrogen atoms in 0.050 mol of C₃H₈O₃ is

Propane, C₃H₈, is commonly provided as a bottled gas for use as a fuel. In 0.200 mol of propane a. what is the mass of propane? b. what mass of carbon is present? c. how many molecules of C₃H₈ are present? d. how many hydrogen atoms are present?

Tetraphosphorus hexaoxide ( = 219.9 g/mol) is formed by the reaction of phosphorus with oxygen gas. P₄(s) + 3O₂(g)  P₄O₆(s) If a mixture of 75.3 g of phosphorus and 38.7 g of oxygen produce 43.3 g of P₄O₆, what is the percent yield for the reaction?

Balance the following equation: Ca₃(PO₄) ₂(s) + SiO₂(s) + C(s)  CaSiO₃(s) + CO(g) + P₄(s)

Sulfur trioxide can react with atmospheric water vapor to form sulfuric acid that falls as acid rain. Calculate the mass in grams of 3.65 × 10²⁰ molecules of SO₃.

In the combustion analysis of 0.1127 g of glucose (C₆H₁₂O₆) , what mass, in grams, of CO₂ would be produced?

How many atoms are in a drop of mercury that has a diameter of 1.0 mm? (Volume of a sphere is 4r³/3; density of mercury = 13.6 g/cm³)

Balance the equation B₂O₃(s) + NaOH(aq)  Na₃BO₃(aq) + H₂O(l)

Aluminum oxide, Al₂O₃, is used as a filler for paints and varnishes as well as in the manufacture of electrical insulators. Calculate the number of moles in 47.51 g of Al₂O₃.

Analysis of a white solid produced in a reaction between chlorine and phosphorus showed that it contained 77.44% chlorine and 22.56% phosphorus. What is its empirical formula?

Balance the following equation for partial oxidation of ammonia, an important reaction in the production of nitric acid: NH₃(g) + O₂(g)  NO(g) + H₂O(l)

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

Lead (II) nitrate is a poisonous substance which has been used in the manufacture of special explosives and as a sensitizer in photography. Calculate the mass of lead in 139 g of Pb(NO₃) ₂.

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

Exam 3: Stoichiometry of Formulas and Equations

Hydroxylamine nitrate contains 29.17 mass % N, 4.20 mass % H, and 66.63 mass O. If its molar mass is between 94 and 98 g/mol, what is its molecular formula?

Aluminum sulfate, Al2(SO4) 3, is used in tanning leather, purifying water, and manufacture of antiperspirants. Calculate its molar mass.

An important reaction sequence in the industrial production of nitric acid is the following: N2(g) + 3H2(g)  2NH3(g) 4NH3(g) + 5O2(g)  4NO(g) + 6H2O(l) Starting from 20.0 mol of nitrogen gas in the first reaction, how many moles of oxygen gas are required in the second one?

Ammonia will react with fluorine to produce dinitrogen tetrafluoride and hydrogen fluoride (used in production of aluminum, in uranium processing, and in frosting of light bulbs) . 2NH3(g) + 5F2(g)  N2F4(g) + 6HF(g) How many moles of NH3 are needed to react completely with 13.6 mol of F2?

The number of hydrogen atoms in 0.050 mol of C3H8O3 is

Propane, C3H8, is commonly provided as a bottled gas for use as a fuel. In 0.200 mol of propane a. what is the mass of propane? b. what mass of carbon is present? c. how many molecules of C3H8 are present? d. how many hydrogen atoms are present?

Tetraphosphorus hexaoxide ( = 219.9 g/mol) is formed by the reaction of phosphorus with oxygen gas. P4(s) + 3O2(g)  P4O6(s) If a mixture of 75.3 g of phosphorus and 38.7 g of oxygen produce 43.3 g of P4O6, what is the percent yield for the reaction?

Balance the following equation: Ca3(PO4) 2(s) + SiO2(s) + C(s)  CaSiO3(s) + CO(g) + P4(s)

Sulfur trioxide can react with atmospheric water vapor to form sulfuric acid that falls as acid rain. Calculate the mass in grams of 3.65 × 1020 molecules of SO3.

In the combustion analysis of 0.1127 g of glucose (C6H12O6) , what mass, in grams, of CO2 would be produced?

How many atoms are in a drop of mercury that has a diameter of 1.0 mm? (Volume of a sphere is 4r3/3; density of mercury = 13.6 g/cm3)

Balance the equation B2O3(s) + NaOH(aq)  Na3BO3(aq) + H2O(l)

Aluminum oxide, Al2O3, is used as a filler for paints and varnishes as well as in the manufacture of electrical insulators. Calculate the number of moles in 47.51 g of Al2O3.

Analysis of a white solid produced in a reaction between chlorine and phosphorus showed that it contained 77.44% chlorine and 22.56% phosphorus. What is its empirical formula?

Balance the following equation for partial oxidation of ammonia, an important reaction in the production of nitric acid: NH3(g) + O2(g)  NO(g) + H2O(l)

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

Lead (II) nitrate is a poisonous substance which has been used in the manufacture of special explosives and as a sensitizer in photography. Calculate the mass of lead in 139 g of Pb(NO3) 2.

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

Aluminum sulfate, Al₂(SO₄) ₃, is used in tanning leather, purifying water, and manufacture of antiperspirants. Calculate its molar mass.

An important reaction sequence in the industrial production of nitric acid is the following: N₂(g) + 3H₂(g)  2NH₃(g) 4NH₃(g) + 5O₂(g)  4NO(g) + 6H₂O(l) Starting from 20.0 mol of nitrogen gas in the first reaction, how many moles of oxygen gas are required in the second one?

The number of hydrogen atoms in 0.050 mol of C₃H₈O₃ is

Propane, C₃H₈, is commonly provided as a bottled gas for use as a fuel. In 0.200 mol of propane a. what is the mass of propane? b. what mass of carbon is present? c. how many molecules of C₃H₈ are present? d. how many hydrogen atoms are present?

Tetraphosphorus hexaoxide ( = 219.9 g/mol) is formed by the reaction of phosphorus with oxygen gas. P₄(s) + 3O₂(g)  P₄O₆(s) If a mixture of 75.3 g of phosphorus and 38.7 g of oxygen produce 43.3 g of P₄O₆, what is the percent yield for the reaction?

Balance the following equation: Ca₃(PO₄) ₂(s) + SiO₂(s) + C(s)  CaSiO₃(s) + CO(g) + P₄(s)

Sulfur trioxide can react with atmospheric water vapor to form sulfuric acid that falls as acid rain. Calculate the mass in grams of 3.65 × 10²⁰ molecules of SO₃.

In the combustion analysis of 0.1127 g of glucose (C₆H₁₂O₆) , what mass, in grams, of CO₂ would be produced?

How many atoms are in a drop of mercury that has a diameter of 1.0 mm? (Volume of a sphere is 4r³/3; density of mercury = 13.6 g/cm³)

Balance the equation B₂O₃(s) + NaOH(aq)  Na₃BO₃(aq) + H₂O(l)

Aluminum oxide, Al₂O₃, is used as a filler for paints and varnishes as well as in the manufacture of electrical insulators. Calculate the number of moles in 47.51 g of Al₂O₃.

Balance the following equation for partial oxidation of ammonia, an important reaction in the production of nitric acid: NH₃(g) + O₂(g)  NO(g) + H₂O(l)

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

Lead (II) nitrate is a poisonous substance which has been used in the manufacture of special explosives and as a sensitizer in photography. Calculate the mass of lead in 139 g of Pb(NO₃) ₂.