Calculate the mass of aluminum required to replace all copper from 135 g of a solution with a mass fraction

Calculate the mass of aluminum required to replace all copper from 135 g of a solution with a mass fraction of copper (II) chlorite of 8%

Given:
m solution (CuCl2) = 135 g
ω (CuCl2) = 8%

To find:
m (Al) -?

Solution:
1) 2Al + 3CuCl2 => 2AlCl3 + 3Cu ↓;
2) m (CuCl2) = ω (CuCl2) * m solution (CuCl2) / 100% = 8% * 135/100% = 10.8 g;
3) n (CuCl2) = m (CuCl2) / M (CuCl2) = 10.8 / 135 = 0.08 mol;
4) n (Al) = n (CuCl2) * 2/3 = 0.08 * 2/3 = 0.05 mol;
5) m (Al) = n (Al) * M (Al) = 0.05 * 27 = 1.35 g.

Answer: The mass of Al is 1.35 g.