How many volumes does 13 g of acetylene take?

13 g acetylene – this will be the mass of the substance, denoted by a small letter m
n – amount of substance
M is the molar mass of the substance
V – volume
you need to find first a large M, then the amount of substance, and then the volume
decision:
M = (12 * 2 + 1 * 2) = 26 (g / mol)
n = m / M = 13/26 = 0.5 (mol)
V = n * V (m) = 0.5 * 22.4 = 11.2 (l)
answer: 11.2 l