Question 1

How many moles of carbon dioxide are there in 52.06 g of carbon dioxide?

Accepted Answer

A) 0.8452 
B) 1.183 
C) 6.022 × 1023 
D) 8.648 × 1023 
E) 3.134 × 1025

Question 2

The formula weight of PbCO3 is ________ amu.

Accepted Answer

A) 279.2 
B) 112.0 
C) 118.0 
D) 267.2 
E) 235.2

Question 3

Under appropriate conditions, nitrogen and hydrogen undergo a combination reaction to yield ammonia: N2 (g) + 3H2 (g) → 2NH3 (g)
A 7.1-g sample of N2 requires ________ g of H2 for complete reaction.

Accepted Answer

A) 0.51 
B) 0.76 
C) 1.2 
D) 1.5 
E) 17.2

Question 4

When the following equation is balanced, the coefficient of water is ________. K (s) + H2O (l) → KOH (aq) + H2 (g)

Accepted Answer

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

Question 5

The molecular weight of ethanol (C2H5OH), rounded to one decimal place, is ________ amu.

Accepted Answer

A) 45.1 
B) 26.0 
C) 25.0 
D) 46.1 
E) 29.0

Question 6

A nitrogen oxide is 63.65% by mass nitrogen. The molecular formula could be ________.

Accepted Answer

A) NO 
B) NO2 
C) N2O 
D) N2O4 
E) either NO2 or N2O4

Question 7

When the following equation is balanced, the coefficient of H2O is ________. Ca (s) + H2O (l) → Ca(OH)2 (aq) + H2 (g)

Accepted Answer

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

Question 8

There are ________ hydrogen atoms in 25 molecules of C4H4S2.

Accepted Answer

A) 25 
B) 3.8 × 1024 
C) 6.0 × 1025 
D) 100 
E) 1.5 × 1025

Question 9

Sulfur and fluorine react in a combination reaction to produce sulfur hexafluoride: S (s) + 3F2 (g) → SF6 (g)
The maximum amount of SF6 that can be produced from the reaction of 3.5 g of sulfur with 4.5 g of fluorine is ________ g.

Accepted Answer

A) 12 
B) 3.2 
C) 5.8 
D) 16 
E) 8.0

Question 10

The molecular weight of the acetic acid (CH3CO2H), rounded to the nearest integer, is ________ amu.

Accepted Answer

A) 60 
B) 48 
C) 44 
D) 32

Question 11

When the following equation is balanced, the coefficient of hydrogen is ________. K (s) + H2O (l) → KOH (aq) + H2 (g)

Accepted Answer

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

Question 12

When the following equation is balanced, the coefficient of H2SO4 is ________. H2SO4 (aq) + NaOH (aq) → Na2SO4 (aq) + H2O (l)

Accepted Answer

A) 1 
B) 2 
C) 3 
D) 4 
E) 0.5

Question 13

Lithium and nitrogen react to produce lithium nitride: 6Li (s)+ N2 (g) → 2Li3N (s)
How many moles of N2 are needed to react with 0.550 mol of lithium?

Accepted Answer

A) 3.30 
B) 0.550 
C) 0.183 
D) 1.65 
E) 0.0917

Question 14

How many grams of hydrogen are in 46 g of CH4O?

Accepted Answer

A) 5.8 
B) 1.5 
C) 2.8 
D) 0.36 
E) 180

Question 15

Which hydrocarbon pair below has identical mass percentage of C?

Accepted Answer

A) C3H4 and C3H6 
B) C2H4 and C3H4 
C) C2H4 and C4H2 
D) C2H4 and C3H6 
E) none of the above

Question 16

What is the mass in grams of 2.00 × 105 atoms of naturally occurring neon?

Accepted Answer

A) 6.07 × 1019 
B) 9910 
C) 797 
D) 3.32 × 10-19 
E) 4040000

Question 17

How many oxygen atoms are there in 52.06 g of carbon dioxide?

Accepted Answer

A) 1.424 × 1024 
B) 6.022 × 1023 
C) 1.204 × 1024 
D) 5.088 × 1023 
E) 1.018 × 1024

Question 18

What is the maximum mass in grams of NH3 that can be produced by the reaction of 1.0 g of N2 with 3.0 g of H2 via the equation below? N2 (g) + H2 (g) → NH3 (g) (not balanced)

Accepted Answer

A) 2.0 
B) 1.2 
C) 0.61 
D) 17 
E) 4.0

Question 19

When the following equation is balanced, the coefficient of sulfur dioxide is ________. PbS (s) + O2 (g) → PbO (s) + SO2 (g)

Accepted Answer

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

Question 20

Lithium and nitrogen react in a combination reaction to produce lithium nitride: 6Li (s)+ N2 (g) → 2Li3N (s)
How many moles of lithium are needed to produce 0.45 mol of Li3N when the reaction is carried out in the presence of excess nitrogen?

Accepted Answer

A) 0.23 
B) 1.4 
C) 0.15 
D) 0.30 
E) 2.7

Exam 3: Stoichiometry: Calculations With Chemical Formulas and Equations

How many moles of carbon dioxide are there in 52.06 g of carbon dioxide?

The formula weight of PbCO₃ is ________ amu.

Under appropriate conditions, nitrogen and hydrogen undergo a combination reaction to yield ammonia: N₂ (g) + 3H₂ (g) → 2NH₃ (g) A 7.1-g sample of N₂ requires ________ g of H₂ for complete reaction.

When the following equation is balanced, the coefficient of water is ________. K (s) + H₂O (l) → KOH (aq) + H₂ (g)

The molecular weight of ethanol (C₂H₅OH) , rounded to one decimal place, is ________ amu.

A nitrogen oxide is 63.65% by mass nitrogen. The molecular formula could be ________.

When the following equation is balanced, the coefficient of H₂O is ________. Ca (s) + H₂O (l) → Ca(OH) ₂(aq) + H₂ (g)

There are ________ hydrogen atoms in 25 molecules of C₄H₄S₂.

Sulfur and fluorine react in a combination reaction to produce sulfur hexafluoride: S (s) + 3F₂ (g) → SF₆ (g) The maximum amount of SF₆ that can be produced from the reaction of 3.5 g of sulfur with 4.5 g of fluorine is ________ g.

The molecular weight of the acetic acid (CH₃CO₂H) , rounded to the nearest integer, is ________ amu.

When the following equation is balanced, the coefficient of hydrogen is ________. K (s) + H₂O (l) → KOH (aq) + H₂ (g)

When the following equation is balanced, the coefficient of H₂SO₄ is ________. H₂SO₄ (aq) + NaOH (aq) → Na₂SO₄ (aq) + H₂O (l)

Lithium and nitrogen react to produce lithium nitride: 6Li (s) + N₂ (g) → 2Li₃N (s) How many moles of N₂ are needed to react with 0.550 mol of lithium?

How many grams of hydrogen are in 46 g of CH₄O?

Which hydrocarbon pair below has identical mass percentage of C?

What is the mass in grams of 2.00 × 10⁵ atoms of naturally occurring neon?

How many oxygen atoms are there in 52.06 g of carbon dioxide?

What is the maximum mass in grams of NH₃ that can be produced by the reaction of 1.0 g of N₂ with 3.0 g of H₂ via the equation below? N₂(g) + H₂ (g) → NH₃ (g) (not balanced)

When the following equation is balanced, the coefficient of sulfur dioxide is ________. PbS (s) + O₂ (g) → PbO (s) + SO₂ (g)

Lithium and nitrogen react in a combination reaction to produce lithium nitride: 6Li (s) + N₂ (g) → 2Li₃N (s) How many moles of lithium are needed to produce 0.45 mol of Li₃N when the reaction is carried out in the presence of excess nitrogen?

Exam 3: Stoichiometry: Calculations With Chemical Formulas and Equations

How many moles of carbon dioxide are there in 52.06 g of carbon dioxide?

The formula weight of PbCO3 is ________ amu.

Under appropriate conditions, nitrogen and hydrogen undergo a combination reaction to yield ammonia: N2 (g) + 3H2 (g) → 2NH3 (g) A 7.1-g sample of N2 requires ________ g of H2 for complete reaction.

When the following equation is balanced, the coefficient of water is ________. K (s) + H2O (l) → KOH (aq) + H2 (g)

The molecular weight of ethanol (C2H5OH) , rounded to one decimal place, is ________ amu.

A nitrogen oxide is 63.65% by mass nitrogen. The molecular formula could be ________.

When the following equation is balanced, the coefficient of H2O is ________. Ca (s) + H2O (l) → Ca(OH) 2 (aq) + H2 (g)

There are ________ hydrogen atoms in 25 molecules of C4H4S2.

Sulfur and fluorine react in a combination reaction to produce sulfur hexafluoride: S (s) + 3F2 (g) → SF6 (g) The maximum amount of SF6 that can be produced from the reaction of 3.5 g of sulfur with 4.5 g of fluorine is ________ g.

The molecular weight of the acetic acid (CH3CO2H) , rounded to the nearest integer, is ________ amu.

When the following equation is balanced, the coefficient of hydrogen is ________. K (s) + H2O (l) → KOH (aq) + H2 (g)

When the following equation is balanced, the coefficient of H2SO4 is ________. H2SO4 (aq) + NaOH (aq) → Na2SO4 (aq) + H2O (l)

Lithium and nitrogen react to produce lithium nitride: 6Li (s) + N2 (g) → 2Li3N (s) How many moles of N2 are needed to react with 0.550 mol of lithium?

How many grams of hydrogen are in 46 g of CH4O?

Which hydrocarbon pair below has identical mass percentage of C?

What is the mass in grams of 2.00 × 105 atoms of naturally occurring neon?

How many oxygen atoms are there in 52.06 g of carbon dioxide?

What is the maximum mass in grams of NH3 that can be produced by the reaction of 1.0 g of N2 with 3.0 g of H2 via the equation below? N2 (g) + H2 (g) → NH3 (g) (not balanced)

When the following equation is balanced, the coefficient of sulfur dioxide is ________. PbS (s) + O2 (g) → PbO (s) + SO2 (g)

Lithium and nitrogen react in a combination reaction to produce lithium nitride: 6Li (s) + N2 (g) → 2Li3N (s) How many moles of lithium are needed to produce 0.45 mol of Li3N when the reaction is carried out in the presence of excess nitrogen?

The formula weight of PbCO₃ is ________ amu.

Under appropriate conditions, nitrogen and hydrogen undergo a combination reaction to yield ammonia: N₂ (g) + 3H₂ (g) → 2NH₃ (g) A 7.1-g sample of N₂ requires ________ g of H₂ for complete reaction.

When the following equation is balanced, the coefficient of water is ________. K (s) + H₂O (l) → KOH (aq) + H₂ (g)

The molecular weight of ethanol (C₂H₅OH) , rounded to one decimal place, is ________ amu.

When the following equation is balanced, the coefficient of H₂O is ________. Ca (s) + H₂O (l) → Ca(OH) ₂(aq) + H₂ (g)

There are ________ hydrogen atoms in 25 molecules of C₄H₄S₂.

Sulfur and fluorine react in a combination reaction to produce sulfur hexafluoride: S (s) + 3F₂ (g) → SF₆ (g) The maximum amount of SF₆ that can be produced from the reaction of 3.5 g of sulfur with 4.5 g of fluorine is ________ g.

The molecular weight of the acetic acid (CH₃CO₂H) , rounded to the nearest integer, is ________ amu.

When the following equation is balanced, the coefficient of hydrogen is ________. K (s) + H₂O (l) → KOH (aq) + H₂ (g)

When the following equation is balanced, the coefficient of H₂SO₄ is ________. H₂SO₄ (aq) + NaOH (aq) → Na₂SO₄ (aq) + H₂O (l)

Lithium and nitrogen react to produce lithium nitride: 6Li (s) + N₂ (g) → 2Li₃N (s) How many moles of N₂ are needed to react with 0.550 mol of lithium?

How many grams of hydrogen are in 46 g of CH₄O?

What is the mass in grams of 2.00 × 10⁵ atoms of naturally occurring neon?

What is the maximum mass in grams of NH₃ that can be produced by the reaction of 1.0 g of N₂ with 3.0 g of H₂ via the equation below? N₂(g) + H₂ (g) → NH₃ (g) (not balanced)

When the following equation is balanced, the coefficient of sulfur dioxide is ________. PbS (s) + O₂ (g) → PbO (s) + SO₂ (g)

Lithium and nitrogen react in a combination reaction to produce lithium nitride: 6Li (s) + N₂ (g) → 2Li₃N (s) How many moles of lithium are needed to produce 0.45 mol of Li₃N when the reaction is carried out in the presence of excess nitrogen?