Chemistry 5070 · O Level · Formulae

Formulae — practice question

W is a compound made up of carbon, hydrogen and oxygen.
(a)[3]

By mass, W is 57.1% carbon and 4.8% hydrogen. Calculate the empirical formula of W.

(b)[3]

A sample of W with a mass of 0.194 g reacts fully with 18.5 cm$^3$ of 0.250 mol/dm$^3$ KOH. One mole of W reacts with three moles of KOH. Calculate the relative formula mass of W.

(c)[1]

Deduce W's molecular formula.

Worked solution & mark scheme

This 7-mark question has a full step-by-step worked solution and mark scheme. One marking point: Calculate the oxygen percentage

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