Practice Percent Yield in Chemistry

Use these practice problems to test your method after reviewing the concept explanation and worked examples.

Worksheet PDF Free Answer-key PDF Family

Quick Recap

The ratio of the actual yield obtained in an experiment to the theoretical yield predicted by stoichiometry, expressed as a percentage.

How much of the possible product you actually got — 100% is perfect, real reactions are always less.

Showing a random 20 of 50 problems.

Example 1

easy
If the theoretical yield is 25.025.0 g and the percent yield is 90.0%90.0\%, what is the actual yield?

Example 2

hard
In C3H8+5O2→3CO2+4H2O\text{C}_3\text{H}_8 + 5\text{O}_2 \rightarrow 3\text{CO}_2 + 4\text{H}_2\text{O}, burning 44 g propane (M=44) with excess O2\text{O}_2 gives 105.6 g CO2\text{CO}_2 (M=44). Percent yield?

Example 3

medium
In N2+3H2→2NH3N_2 + 3H_2 \rightarrow 2NH_3, 1 mol N2N_2 (excess H2H_2) gives 28.9 g NH3NH_3 (M=17M=17). Percent yield?

Example 4

challenge
In N2+3H2→2NH3\text{N}_2 + 3\text{H}_2 \rightarrow 2\text{NH}_3, you start with 28 g N2\text{N}_2 (M=28) and 4 g H2\text{H}_2 (M=2). Identify the limiting reactant, then compute percent yield if 10.2 g NH3\text{NH}_3 (M=17) is collected.

Example 5

easy
Which reactant determines the theoretical yield: limiting or excess?

Example 6

challenge
In C+O2→CO2C + O_2 \rightarrow CO_2 with 6 g C (M=12M=12) and 8 g O2O_2 (M=32M=32), 8.8 g CO2CO_2 forms (M=44M=44). Percent yield?

Example 7

easy
Actual 3 g, theoretical 12 g. Percent yield?

Example 8

medium
A reaction has 85% yield and a theoretical yield of 200 g. What actual mass is expected?

Example 9

medium
If the actual yield equals the theoretical yield, the percent yield is ____.

Example 10

easy
A reaction's percent yield is 80% and actual yield is 16 g. What was the theoretical yield?

Example 11

medium
In S+O2→SO2\text{S} + \text{O}_2 \rightarrow \text{SO}_2, 32 g S (M=32) with excess O2\text{O}_2 gives 51.2 g SO2\text{SO}_2 (M=64). Percent yield?

Example 12

easy
True or false: percent yield can usually exceed 100% in a well-run experiment.

Example 13

medium
Percent yield is 60% and actual yield is 30 g. What was the theoretical yield?

Example 14

medium
Percent yield is 50% and theoretical yield is 80 g. What is the actual yield?

Example 15

challenge
A chemist wants an overall yield of at least 50% over 3 equal-yield steps. What is the minimum yield each step must achieve?

Example 16

easy
Can percent yield exceed 100%? What does it usually mean?

Example 17

medium
In C+O2→CO2C + O_2 \rightarrow CO_2, 12 g C (M=12M=12) gives 33 g CO2CO_2 (M=44M=44). Percent yield?

Example 18

medium
A reaction is reported with 65% yield. Theoretical yield is 80 g. Actual yield?

Example 19

medium
In CaCO3→CaO+CO2CaCO_3 \rightarrow CaO + CO_2, 100 g CaCO3CaCO_3 (M=100M=100) gives 42 g CaOCaO (M=56M=56). Percent yield?

Example 20

medium
Three reaction steps each have 90% yield. Overall percent yield?
← Back to Percent Yield Worked Examples Formula Explained

Related Concepts

Theoretical Yield