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CaCN2 + 3H2O - CaCO3 + 2NH3 .

How much CaCO3 is produced upon reaction of 45 g CaCN2 and 45 g of H2O?

1. 250 g

2. 38 g

3. 19 g

4. 750 g

5. 28 g

6. 83 g

7. 56 g

Consider the reaction

N2 + 3H2 - 2NH3 .

How much NH3 can be produced from the

reaction of 74.2 g of N2 and 14.0 moles of H2?

1. 5.62 × 1024 molecules

2. 3.19 × 1024 molecules

3. 1.26 × 1025 molecules

4. 1.59 × 1024 molecules

5. 1.69 × 1025 molecules

In the reaction below, 22 g of H2S with excess O2 produced 7 g of sulfur.

?H2S + ?O2 - ? S + ?H2O.

What is the percent yield of sulfur? Answer

in units of %.

Consider the following reaction:

CaCN2 + 3H2O - CaCO3 + 2NH3

105.0 g CaCN2 and 78.0 g H2O are reacted.

Assuming 100% efficiency, which reactant is in excess and how much is leftover? The molar mass of CaCN2 is 80.11 g/mol. The

molar mass of CaCO3 is 100.09 g/mol.

1. CaCN2; 70.8 g left over

2. H2O; 70.8 g left over

3. H2O; 10.7 g left over

4. CaCN2; 7.20 g left over

5. CaCN2; 10.7 g left over

6. H2O; 7.20 g left over

Consider the following reaction.

N2 + 3H2 - 2NH3 .

28.0 grams of N2 and 5.04 grams of H2 are

reacted, producing 17.8 grams of NH3. What

is the percent yield?

1. 34.0%

2. 14.7%

3. 62.9%

4. 52.4%

5. Not enough information is given.

6. 84.0%

7. 191%