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Chemistry moles calculation help

Hi need urgent help with this question.

31.6% carbon
5.3% hydrogen
63.1% oxygen
a) What is the empirical formula of acid X?
b) an aqueous solution contains 11.4 g of X per dm^3. 20 cm^3 of this solution required 30cm^3 of 0.1 mol dm^-3 NaOH for reaction in a titration. calculate the relative molecular mass of the acid
c) deduce the dull structural formula of X

Reply 1

Aiko chan

c) deduce the *full* structural formula of X

Reply 2

8013

a) Default the volume of solution to 100 g, then calculate the number of moles of each element and the mole ratio.
(Answer: C2H3O4)
b) Volume of NaOH=30/1000*0.1=0.003
Concentration of acid X=0.003/(20/1000)=0.15 M
Relative molecular mass=11.4/0.15=76
c) CH2COOOOH