Question

Calculate the molecular formula of a compound whose empirical formula is CH2O and vapour density is 30.

August 2, 2024

Answer

Empirical formula is CH₂O

Empirical formula weight = 12 + 2(1) + 16

= 12 + 2 + 16

= 30

Vapour density (V.D.) = 30

Molecular weight = 2 × V.D. = 2 × 30 = 60

n = $Molecular\ weight\over Emperical\ Formula\ Weight$

= $60\over 30$

= 2

Molecular formula = (CH₂O)₂ = C₂H₄O₂

Hence, Molecular formula is C₂H₄O₂

💡 Some Related Questions

Copper [II] sulphate soln. reacts with sodium hydroxide soln. to form copper hydroxide according to the equation :
2NaOH + CuSO4 ⟶ Na2SO4 + Cu(OH)2↓
What mass of copper hydroxide is precipitated by using 200 g of sodium hydroxide.
[H = 1, O = 16, Na = 23, S = 32, Cu = 64]

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Al4C3 + 12H2O ⟶ 4Al(OH)3 + 3CH4
(i) State what mass of aluminium hydroxide is formed from 12 g. of aluminium carbide.
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