10 g of hydrofluoric acid gas occupies 5.6 L of volume at STP. If the empirical formula of the gas is HF, then its molecular formula in the gaseous state will be

Question

10 g of hydrofluoric acid gas occupies 5.6 L of volume at STP. If the empirical formula of the gas is HF, then its molecular formula in the gaseous state will be (A) HF (B) H2F2 (C) H3F3 (D) H4F4

Tardigrade Admin · Accepted Answer

Mol. mass = mass of 22.4 L at STP =(10/5.6)×22.4=4 E.F. mass of HF = 1 + 19 = 20. Hence n=(40/20)=2 ∴ Molecular formula = (Empirical formula)n =(HF)2=H2F2

Q. 10 g of hydrofluoric acid gas occupies 5.6 L of volume at STP. If the empirical formula of the gas is HF, then its molecular formula in the gaseous state will be

$H F$

$H_{2} F_{2}$

$H_{3} F_{3}$

$H_{4} F_{4}$

Mol. mass = mass of 22.4 L at STP
$= \frac{10}{5.6} \times 22.4 = 4$
$E . F .$ mass of $H F = 1 + 19 = 20$ .
Hence $n = \frac{40}{20} = 2$
$∴$ Molecular formula = (Empirical formula) $_{n}$
$= (H F)_{2} = H_{2} F_{2}$

Q. 10 g of hydrofluoric acid gas occupies 5.6 L of volume at STP. If the empirical formula of the gas is HF, then its molecular formula in the gaseous state will be

HF

H2​F2​

H3​F3​

H4​F4​

Mol. mass = mass of 22.4 L at STP =5.610​×22.4=4 E.F. mass of HF=1+19=20. Hence n=2040​=2 ∴ Molecular formula = (Empirical formula)n​ =(HF)2​=H2​F2​

$H F$

$H_{2} F_{2}$

$H_{3} F_{3}$

$H_{4} F_{4}$

Mol. mass = mass of 22.4 L at STP
$= \frac{10}{5.6} \times 22.4 = 4$
$E . F .$ mass of $H F = 1 + 19 = 20$ .
Hence $n = \frac{40}{20} = 2$
$∴$ Molecular formula = (Empirical formula) $_{n}$
$= (H F)_{2} = H_{2} F_{2}$