Question

A compound of X and Y has the empirical formula XY2. It’s vapour density is equal to it’s empirical formula weight. Determine it’s molecular formula.

August 5, 2024

Answer

Empirical formula = XY₂

Empirical formula weight = V.D.

Molecular weight = 2 × V.D.

n = $Molecular\ weight\over Empirical\ formula\ weight$

= $2 × VD\over VD$ = 2

∴ Molecular formula = 2(XY₂)₂ = X₂Y₄

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