GCSE Chemistry Percentage Mass Calculations

What is the % by mass of O in H₂O

What is the % by mass of O in SO₃

What is the % by mass of Na in Na₂CO₃

% by mass of N in Ca(NO₃)₂

What is the % by mass of O in Ca(NO3)₂

% by mass of Cl in FeCl₃

What is the % by mass of N in NH₄NO₃

What is the % by mass of S in Al₂(SO₄)₃

What is the % by mass of Li in lithium oxide Li₂O

What is the % by mass of Cr in chromium(III) oxide - Cr₂O₃