Question

Polyethene can be produced from calcium carbide according to the following sequence of reactions
`CaC_(2)+2H_(2)OtoCa(OH)_(2)+C_(2)H_(2)`
`C_(2)H_(2)+H_(2)overset(Pd//BaSO_(4)//S" ")(to)C_(2)H_(4)`
`underset("Ethene")(C_(2)H_(4)tounderset("Polythene")[CH_(2)-CH_(2)]n`
Calculate the mass of polyethene produced from 20 kg of `CaCO_(2)`.
A. `18.25` kg
B. `8.75` kg
C. `8.25` kg
D. `28.25` kg

Answer 1

Correct Answer - B
From given equtions
1 mol `underset(64g)("of")` `CaC_(2)=1` mol of `C_(2)H_(2)=1`mol `underset(28g)("of") C_(2)H_(2)`
Mass of `CaC_(2)=20kg = 20xx10^(3)g`
64g of `CaC_(2)=28g` of `C_(2)H_(4)`
`20xx10^(3)`g of `CaC_(2) = ((28g)xx(20xx10^(3)g))/(64g)`
`=8.75xx10^(3)g` of `C_(2)H_(4)`
Mass of polyethene=Mass of ethene
`=8.75xx10^(3)g=8.75kg`