Need answer to this question asap. it is worth 10 points the molar ratio of carbon to hydrogen of a volatile liquid compound is 1.2:0.12 of the liquid. on evaporation at s. t.p gave 32cm3 of vapour. what is the molecular formula of the liquid

The molecular formula of the liquid : C₆H₁₂

Given

molar ratio C H = 1.2 : 0.12

0.12 g at STP gave 32 cm³(0.032 L)

Required

The molecular formula

Solution

At STP, 1 mol = 22.4 L, so for 0.032 L :

mol = 0.032 : 22.4

mol = 0.00143

Molar mass (M) of liquid :

M = mass : mol

M = 0.12 g : 0.00143 mol

M = 83.92≈84 g/mol

C : H = 1 : 2

(CH₂)n=84

(12+2.1)n=84

(14)n=84

n=6

(CH₂)₆=C₆H₁₂

i believe you are right for all except the 3rd ( look at sqdancefan his answer is much better)

the answer to your question is c