Test Index

CBSE Class 10 Science 2019 Outside Delhi Set 3

© examsnet.com
Question : 9
Total: 12
Given below are the steps for the extraction of copper from its ore. Write the chemical equation of the reactions involved in each case.
(i) Roasting of copper(I) sulphide.
(ii) Reduction of copper(I) oxide from copper(I) sulphide
(iii) Electrolytic refining.
Solution:  
(i)
2Cu2S( s)
Copper(I) sulphide
(Copper glance ore)
+
3O2(g)
Oxygen(From air)
‌ Roasting ‌
──────▶
2Cu2O( s)
Copper (I) oxide
+
2SO2(g)
Sulphur dioxide
(ii)
2Cu2O(s)
Copper(I) oxide
+
Cu2S(s)
Copper sulphide
‌ Heat ‌
──────▶
6‌Cu( s)
Copper metal
+
SO2(g)
Silphur dioxide
(iii) (a) At cathode :
Cu2+
Copper ion
(From electrolyte)
+
2e−
Electrons
(From cathode)
→
Cu
Copper
(Deposits on cathode)
(b) At anode :
Cu
Copper atom
(From impure anode)
‌‌−‌‌
2e−
Electrons
(Given to anode)
→
Cu2+
Copper ion
(Goes into electrolyte)
© examsnet.com
Go to Question:
Prev Question
Next Question