2.6 Calculations involving masses

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Question 7

A laboratory analyses a liquid compound, X. The compound contains carbon, hydrogen and oxygen only.

Element	carbon	hydrogen	oxygen
Percentage by mass	52.2%	13.0%	34.8%

Element	H	C	O
Relative atomic mass, $A_r$	1	12	16

Determine the empirical formula of compound X, showing each stage of your calculation.

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Markscheme

2.6 Calculations involving masses Questions

GCSE
Chemistry
2.6 Calculations involving masses

142 exam-style questions on Edexcel GCSE Chemistry 2.6 Calculations involving masses, covering 2.6.1 Relative formula mass and percentage composition, 2.6.2 Empirical and molecular formulae, 2.6.3 Conservation of mass, 2.6.4 Reacting masses and concentration in g dm⁻³, 2.6.5 The mole and the Avogadro constant, and 2.6.6 Limiting reactants and stoichiometry. Each one has a worked solution and a mark scheme showing where the marks go.

Question bank·2.6 Calculations involving masses