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Worksheet on Stoichiometry (Show all required parts)

Use the following to answer questions 1 & 2.

NaCl + MgO  Na2O + MgCl2

1. If 24 grams of sodium chloride reacts with an excess amount of magnesium oxide, how many grams of sodium oxide will be produced?

2. If 53 grams of magnesium oxide reacts with an excess amount of sodium chloride, how many grams of magnesium chloride will be made?

Use the following to answer questions 3 & 4.

Mg3N2 + K2O  MgO + K3N

3. If 14 moles of potassium oxide reacts with an excess amount of magnesium nitride, how many grams of potassium nitride will be made?

4. How many grams of magnesium nitride is needed to react with an excess amount of potassium oxide to produce 11.6 grams of magnesium oxide?

Use the following to answer questions 5 - 8.

C3H8 + O2  H2O + CO2

5. 32 grams of propane (C3H8) is burned in excess oxygen gas to produce how many grams of water?

6. How many grams of oxygen gas is needed to make 30 grams of carbon dioxide?

7. If 0.45 grams of water is formed during the combustion of propane, how many grams of carbon dioxide is formed?

8. How many grams of propane, C3H8, are needed to make 140 grams of water?

Worksheet on Stoichiometry (Show all required parts)

Use the following to answer questions 1 & 2.

2 NaCl + MgO  Na2O + MgCl2

1. If 24 grams of sodium chloride reacts with an excess amount of magnesium oxide, how many grams of sodium oxide will be produced?

A B

Given: 24 g NaCl = ? grams Na2O

Conversions: Molar mass of NaCl: 1 mole NaCl = 58 g NaCl

Mole to mole ratio: 2 mole NaCl = 1 mole Na2O

Molar mass of Na2O: 1 mole Na2O = 62 g Na2O

Setup:

24 g NaCl X 1 mole NaCl X 1 mole Na2O X 62 g Na2O = 12.8 g Na2O

58 grams NaCl 2 mole NaCl 1 mole Na2O

2. If 53 grams of magnesium oxide reacts with an excess amount of sodium chloride, how many grams of magnesium chloride will be made?

A B

Given: 53 g MgO = ? g MgCl2

Conversions: Molar mass of MgO: 1 mole MgO = 40 g MgO

Mole to Mole Ratio : 1 mole MgO = 1 mole MgCl2

Molar mass of MgCl2 : 1 mole MgCl2 = 94 g MgCl2

Setup:

53 g MgO X 1 mole MgO X 1 mole MgCl2 X 94 g MgCl2 = 124.55 g MgCl2

40 g MgO 1 mole MgO 1 mole MgCl;2

Use the following to answer questions 3 & 4.

Mg3N2 + 3 K2O  3 MgO + 2 K3N

3. If 14 moles of potassium oxide reacts with an excess amount of magnesium nitride, how many grams of potassium nitride will be made?

AB

Given: 14 grams K2O = ? g K3N

Conversions: Molar mass of K2O: 1 mole K2O = 94 g K2O

Mole to mole ratio: 3 moles K2O = 2 moles K3N

Molar mass K3N: 1 mole K3N = 131 g K3N

Setup:

14 grams K2O X 1 mole K2O X 2 moles K3N X 131 g K3N = 13 g K3N

94 g K2O 3 moles K2O 1 mole K3N

4. How many grams of magnesium nitride is needed to react with an excess amount of potassium oxide to produce 11.6 grams of magnesium oxide?

A B

Given: 11.6 grams MgO = ? g Mg3N2

Conversions: Molar mass of MgO: 1 mole MgO = 40 g MgO

Mole to mole ratio: 3 moles MgO = 1 mole Mg3N2

Molar mass Mg3N2: 1 mole Mg3N2 = 100 g Mg3N2

Setup:

11.6 grams MgO X 1 mole MgO X 1 mole Mg3N2 X 100 g Mg3N2 = 9.7 g Mg3N2

40 g MgO 3 moles MgO 1 mole Mg3N2

Use the following to answer questions 5 - 8.

C3H8 + 5 O2  4 H2O + 3 CO2

5. 32 grams of propane (C3H8) is burned in excess oxygen gas to produce how many grams of water?

A B

Given: 32 g C3H8 = ? g H2O

Conversions: Molar mass C3H8 : 1 mole C3H8 = 44 g C3H8

Mole to Mole ratio: 1 mole C3H8 = 4 moles H2O

Molar mass H2O : 1 mole H2O = 18 g H2O

Setup:

32 g C3H8 X 1 mole C3H8 X 4 moles H2O X 18 g H2O = 52.4 g H2O

44 g C3H8 1 mole C3H8 1 mole H2O

6. How many grams of oxygen gas is needed to make 30 grams of carbon dioxide?

A B

Given: 30 g CO2 = ? g O2

Conversions: Molar mass CO2 : 1 mole CO2 = 44 g CO2

Mole to mole ratio: 3 moles CO2 = 5 moles O2

Molar mass of O2 : 1 mole O2 = 32 g O2

Setup:

30 g CO2 X 1 mole CO2 X 5 moles O2 X 32 g O2 = 36.4 g O2

44 g CO2 3 moles CO2 1 mole O2

7. If 0.45 grams of water is formed during the combustion of propane, how many grams of carbon dioxide is formed?

A B

Given: 0.45 g H2O = ? grams CO2

Conversions: Molar mass of H2O: 1 mole H2O = 18 g H2O

Mole to mole ratio: 4 moles H2O = 3 moles CO2

Molar mass of CO2 : 1 mole CO2 = 44 g CO2

Setup:

0.45 g H2O X 1 mole H2O X 3 moles CO2 X 44 g CO2 = .825 g CO2

18 g H2O 4 moles H2O 1 mole CO2

8. How many grams of propane, C3H8, are needed to make 140 grams of water?

A B

Given: 140 g H2O = ? g C3H8

Conversions: Molar mass H2O: 1 mole H2O = 18 g H2O

Mole to mole ratio: 4 moles H2O = 1 mole C3H8

Molar mass C3H8 : 1 mole C3H8 = 44 g C3H8

Setup:

140 g H2O X 1 mole H2O X 1 mole C3H8 X 44 g C3H8 = 85.4 g C3H8

18 g H2O 4 moles H2O 1 mole C3H8