Percent Yield Calculation

Chemistry Tutorial

Percent Yield Calculation


When given the mass of one reactant and the mass of the final product, we can use stoichiometry to find the percent yield of the product.

Sample Problem

If 120.7g phosphorous pentachloride (molar mass=208.2g/mol) is formed when 64.2g of chlorine gas (molar mass=70.90g/mol) reacts with excess phosphorous trichloride, calculate the percent yield for the reaction.


Step 1: write out the balanced equation
= PCl3 + Cl2 -> PCl5

Step 2: convert from grams Cl2 to grams PCl5
= 64.2g x 1mol/70.90g x 1molPC5/1molCl2 x 208.2g/1mol = 188.525g

Step 3: calculate percent yield
= 120.7g/188.525g x 100% = 64.02%

About The Author

Science And Math
I am a second year biomedical studies student at UNBC. I have experience being a tutor for subjects such as math, biology, and English from high school when I was part of a peer mentorship tutoring program. I helped younger students with their classes and their understanding of the material.
11 Subjects
KnowRo Tutor
1 Tutorial
Prince George, BC
Get Tutoring Info

Suggested Tutors for Chemistry Help

Altai P

Durham, NH

Science And Math Tutor

Jeff N

Derry, NH

Math and Chemistry demystified

Salme C

Dover, NH

Engineer With Teaching/Tutoring Experience

Paul P

Dover, NH

Math Subject Matter Expert And SAT Instructor