Question

If 0.680 kg of copper(I) sulfide reacts with excess oxygen, what mass of copper metal may be produced ? A) 0.680 kg B) 0.136 kg C) 0.271 kg D) 0.543 kg E) 1.36 kg

Answer 1

Answer:

D. 0.543kg of copper metal is produced from 0.680kg of copper 1 sulphide.

Explanation:

First write the equation for the reaction:

Cu2S + O2 ------> 2Cu + SO2

Determine the mole ratio of the two substances:

I mole of Cu2O forms 2 moles of Copper metal

The number of moles of copper 1 sulphide used is;

n = mass of Cu2S / molar mass of Cu2S

Mass = 0.680kg = 680g

Molar mass = 159.16g/mol

n = 680g / 159.16g/mol

n = 4.272moles

Determine the number of mole of copper:

Number of moles of copper metal produced from 4.272moles of copper 1 sulphide is therefore:

n of copper = 2 * 4.272 Moles

n = 8.544moles.

Determine the mass copper:

The mass of copper metal produced is therefore = number of moles of copper * molar mass of copper

mass = 8.544 moles * 63.55g/mol

mass = 542.97grams

Mass = 0.543kg