If the actual yield is 4.5 g and the theoretical yield is 6.0 g, what is the percent yield?

• A. 50%
• B. 75%
• C. 80%
• D. 60%

Answer: (B)

Percent yield shows how efficient a reaction was by comparing what was actually obtained to what could theoretically be produced. It is calculated as (actual yield / theoretical yield) × 100%. Here, (4.5 g / 6.0 g) × 100% = 0.75 × 100% = 75%. So the percent yield is 75%. If the actual yield were 3.0 g, the percent yield would be 50%; if it were 4.8 g, it would be 80%; if it were 3.6 g, it would be 60%. This illustrates how the percentage directly reflects proximity to the theoretical maximum.