Acetylene was obtained by thermal treatment of methane, with complete bromination

Acetylene was obtained by thermal treatment of methane, with complete bromination of which a bromine derivative with a mass of 173 g was obtained. Calculate the volume of methane that was taken for the reaction.

Let’s compose the equations:
2CH4 = C2H2 + 3H2 – cracking of methane, acetylene obtained;
C2H2 + 2Br2 = C2H4Br4 – complete bromination, tetrabromoethane is released.
Let’s calculate the molar masses:
M (C2H2) = 16 g / mol;
M (C2H4Br4) = 347.6 g / mol.
Let us determine the number of moles of the reaction product if its mass is 173 g:
Y (C2H4Br4) = m / M = 173 / 347.6 = 0.49 mol.
Let’s make the proportion:
X mol (CH4) – 0.5 mol (C2H4Br4);
-2 mol -1 mol hence, X mol (CH4) = 2 * 0.5 / 1 = 1 mol.
We find the volume of the substance:
1 mol (C2H4Br4) at normal conditions occupies a volume of 22.4 liters. according to Avogadro’s law.
Answer: the volume occupied by tetrabromoethane is 22.4 liters.