Question

What mass of acetylene gas, C2H2, would be produced by complete reaction of 3.75g of calcium carbide

Answer 1

 The  mass  of C₂H₂  that  would  be  produced by  complete reaction  of 3.75 g  of  calcium  carbide is  1.524 grams

 calculation

calcium carbide (CaC₂) react with  water(H₂O) to  produce C₂H₂  and Ca(OH)₂  according to  reaction below

CaC₂ +2H₂O   C₂H₂ + Ca(OH)₂

 calculate  the moles of CaC₂

 moles  = mass÷ molar mass

from periodic table the  molar mass   of CaC₂ = 40 + (12 x2) = 64 g/mol

moles is therefore =3.75 g÷ 64 g/mol =0.0586  moles

Use the  mole ratio to determine the  moles of C₂H₂

from equation above  CaC₂: C₂H₂  is 1:1 therefore the  moles of C₂H₂  is also

= 0.0586  moles

mass  of C₂H₂ =  moles x molar mass

from periodic table the  molar mass of C₂H₂  = (12 x 2) + (1 x 2)  = 26 g/mol

mass =0.0586  moles x 26 g/mol =1.524 grams