Percent Composition Calculator

Calculate the mass percent of each element in a compound

Enter Chemical Formula
Use element symbols with numbers (H2O). Parentheses supported: Ca(NO3)2
About
Formula
% Mass = (Element Mass / Total Mass) × 100%
Steps
  1. Find molar mass of compound
  2. Find total mass of each element
  3. Divide element mass by total
  4. Multiply by 100%
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