Percent Yield Calculator

What is Percent Yield?

Percent yield measures the efficiency of a chemical reaction by comparing the actual amount of product obtained (actual yield) to the maximum amount that could be produced (theoretical yield). This calculation is crucial in chemistry labs, industrial processes, and pharmaceutical manufacturing.

Percent Yield Formula

Percent Yield = (Actual Yield ÷ Theoretical Yield) × 100%

How to Calculate Percent Yield

1. Determine the theoretical yield through stoichiometry
2. Measure the actual yield from your reaction
3. Divide actual yield by theoretical yield
4. Multiply by 100 to get percentage

Common Percent Yield Values

• 100%: Perfect yield (rare in practice)
• 90-99%: Excellent yield
• 70-89%: Good yield
• 50-69%: Moderate yield
• Below 50%: Poor yield

Why is Percent Yield Important?

• Measures reaction efficiency
• Identifies process improvements
• Calculates production costs
• Determines reaction feasibility
• Evaluates experimental procedures
• Helps troubleshoot reactions
• Assesses product quality

Examples of Percent Yield Calculations

Example 1: Lab Synthesis

Theoretical Yield: 25.0 g
Actual Yield: 22.5 g
Percent Yield = (22.5 ÷ 25.0) × 100 = 90%

Example 2: Industrial Process

Theoretical Yield: 500 kg
Actual Yield: 425 kg
Percent Yield = (425 ÷ 500) × 100 = 85%

FAQ About Percent Yield

Can percent yield exceed 100%?

Technically no. A yield over 100% indicates experimental error or impurities in the product.

Why is actual yield always less than theoretical?

Due to real-world limitations like incomplete reactions, side products, and mechanical losses.