Question

How much copper can be purified from 750 grams of copper (I) sulfide? Show how you got your answer.

Answer 1

Answer: 598.90 g

Step-by-step explanation:

1) Chemical formula of copper(I) sulfide:
Cu₂S

2) Atomic masses of Cu and S:

Cu: 63.546 g/mol
S: 32.065 g/mol

3) Molar mass of Cu₂S: 2×63.546 g/mol + 32.065 g/mol = 159.157 gmol

4) Mass ratio:

127.092 g Cu / 159.157 g Cu₂S

5) Proportion:

x / 750 g Cu₂S = 127.092 g Cu / 159.157 g Cu₂S

6) Solve for x:

x = [127.092 g Cu / 159.157 g Cu₂S]×750 g Cu₂S = 598.90 g Cu

Answer 2

Answer is: 598.64 grams of copper.

m(Cu₂S) = 750 g; mass of copper(I) sulfide.
M(Cu₂S) = 159,16 g/mol; molar mass of copper(I) sulfide.
n(Cu₂S) = m(Cu₂S) ÷ M(Cu₂S).
n(Cu₂S) = 750 g ÷ 159.16 g/mol.
n(Cu₂S) = 4.71 mol; amount of substance.
There are two atoms of copper in one molecule of copper(I) sulfide:
n(Cu) : n(Cu₂S) = 2 : 1.
n(Cu) = 2 · 4.71 mol.
n(Cu) = 9.42 mol.
m(Cu) = 9.42 mol · 63.55 g/mol.
m(Cu) = 598.64 g; mass of copper.