Question

A 1.1184 g sample of a hydrocarbon is combusted to give 2.1345 g of H20 and 3.2809 g of CO2. (a) How many mol of H and C are in this sample? (b) What's the molar ratio between C and H? (Hint: use x:1 or 1x to represent the ratio) (c) If the moles of this sample is determined to be 0.03728 mol, what is the molecular formula of the compound? TT T Arial : 3 (12pt) + T 5 - 5 - 5.0

Answer 1

Ans: - Let the lydro carbor be a Hy. саны + aty , z co, + ун, о. ca mass of moles of H₂O = 2.1345 g H₂O = 2.1345 = 8.11848 mol 18.015 moles of Hlu H₂O produced sample = 2x moles of = 0.236 96 mol mass of moles of co co = 3.2809g = 3.2809 = 0.0745 mol. 44 moles of c in sample = moles of CO2 0.0745 mol. produced (6] molar ratio of between cond H = moles of coal moles of H₂O = 0.314 : 1 = 1 : 3.182 moles of sample = 0.01728 mol Molecular mass of sample = 1.1184 0.03728 = 30 = 30 ratio es 1:3 Molecular mass of semple = (2x + y since molar n = 1 y 3 x=2 y = 6 compound es qH6