Acetylene gas (C2H2) is produced as a result of the reaction CaC2(s) + 2 H2O(ℓ) → C2H2(g) + Ca(OH)2(aq). If 10 g of CaC2 are consumed in this reaction, how much H2O is needed? Answer in units of mol.

1 Answer
Apr 10, 2018

0.312 mol

Explanation:

First, find the number of moles of #CaC_2# that is used by dividing the mass by the molar mass.

Molar mass: #40.08+2(12.01)=64.1# #gmol^-1#

#(10g)/(64.1gmol^-1)=0.156# #mol# of #CaC_2# reacted

From the stoichiometry, we can see that for every mol of #CaC_2#, 2 mol of #H_2O# is needed

#2 xx 0.156=0.312# #mol# of #H_2O#