From acetylene with a volume of 25 liters, benzene with a mass of 16 g was obtained.
From acetylene with a volume of 25 liters, benzene with a mass of 16 g was obtained. What is the mass fraction of the benzene yield?
Given:
V (C2H2) = 25 l
m (C6H6) = 16 g
Find:
% (practical C6H6) -?
Solution:
3C2H2 – (active coal) -> C6H6, – we solve the problem based on the composed reaction equation:
1) Find the amount of acetylene that has reacted:
n (C2H2) = V: Vm = 25 L: 22.4 L / mol = 1.12 mol
2) We compose a logical expression:
if 3 mol of C2H2 gives 1 mol of C6H6,
then 1.12 mol of C2H2 will give x mol of C6H6,
then x = 0.37 mol.
3) Find the mass of benzene formed during the reaction:
m (C6H6) = n * M = 0.37 mol * 78 g / mol = 28.86 g
4) Find the practical benzene yield:
w% (C6H6 practical) = 16 g: 28.86 g * 100% = 55.4%.
Answer: w% (C6H6 practical) = 55.4%.