A mixture of ethane and ethylene with a volume of 200 ml decolorized bromine water 25 g.

A mixture of ethane and ethylene with a volume of 200 ml decolorized bromine water 25 g. Calculate the volume fraction in the mixture if the mass fraction of bromine in water is 3.2%

Find the mass of Br2 in water.

25 g – 100%,

x g – 3.2%,

x = (3.2% x 25g): 100% = 0.8g.

Let’s find the amount of substance Br2.

M (Br2) = 160 g / mol.

n = 0.5 g: 160 g / mol = 0.005 mol.

C2H4 + Br2 = C2H4Br2

For 1 mole of Br2, there is 1 mole of C2H4. Substances are in quantitative ratios

1: 1 The amount of substance is equal.

n (C2H4) = n (Br2) = 0.005 mol.

Let’s find the volume of C2H4.

V = n Vn, where Vn is the molar volume of gas equal to 22.4 l / mol.

V = 0.005 mol × 22.4 L / mol = 112 ml.

ȹ = (112 ml: 200 ml) × 100% = 56%.

Answer: 56%.