Step 1
The reaction must be completed and balanced:
CaC2 + 2H2O = C2H2 + Ca(OH)2
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Step 2
Information provided:
H2O (water) is the excess.
CaC2 is the limiting reactant. This limits the production of C2H2
Information needed:
The molar mass of CaC2 (64.0 g/mol) and C2H2 (26.0 g/mol)
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Step 3
By stoichiometry:
1 mol CaC2 = 64.0 g
1 molC2H2 = 26.0 g
64.0 g CaC2 -------- 26.0 g C2H2
5.00 g CaC2 -------- X
X = 5.00 g CaC2 x 26 g C2H2/64.0 g CaC2 = 2.03 g C2H2
Answer: 2.03 g C2H2