Answer to Question #233000 in Chemistry for arissa

Question

A hydrocarbon,W with a mass 10.50 g has 17.35% hydrogen. W

undergoes complete combustion.

Calculate the mass (g) of H 2 O formed.

Answer 1

Solution:

hydrocarbon = C_xH_y

Mass of C_xH_y = Mass of C + Mass of H

Mass of H = %H × Mass of C_xH_y

Mass of H = 0.1735 × 10.50 g = 1.82175 g H

The molar mass of H is 1.00784 g/mol.

Hence,

(1.82175 g H) × (1 mol H / 1.00784 g H) = 1.8076 mol H

2yH + yO → yH₂O

Hence,

(1.8076 mol H) × (1 mol H₂O / 2 mol H) = 0.9038 mol H₂O

The molar mass of H₂O is 18.01528 g/mol.

Hence,

(0.9038 mol H₂O) × (18.01528 g H₂O / 1 mol H₂O) = 16.316 g H₂O = 16.32 g H₂O

Mass of H₂O = 16.32 g

Answer: 16.32 grams of H₂O formed.