How many grams of acetylene react if 1.10 mol of co2 are produced?

 Combustion of acetylene :

molar mass acetylene ( C₂H₂ ) = 26.0 g/mol and CO₂ = 44.0 g/mol

2 C₂H₂ + 5 O₂ ---> 4 CO₂ + 2 H₂O

2 moles C₂H₂ > 4 moles CO₂
? moles C₂H₂ > 1.10 moles CO₂

moles C₂H₂ = 1.10 * 2  / 4

moles C₂H₂ = 0.55 moles of C₂H₂

Mass acetylene:

m = n * mm

m = 0.55 * 26.0

m = 14.3 g

hope this helps!