Q7 / 90 · JEE Main 2019 (12 Apr Shift 2) · Chemistry

The correct statement is:

A
Pig iron is obtained from cast iron.
B
The Hall-Heroult process is used for the production of aluminium and iron.
Correct answer
C
leaching of bauxite using concentrated $N a O H$ solution gives sodium aluminate and sodium silicate.
D
the blistered appearance of copper during the metallurgical process is due to the evolution of $C O_{2} .$

Solution

(1) During leaching when bauxite is treated with concentrated

N a O H,

then sodium aluminate and sodium silicate is formed in the soluble form, whereas

F e_{2} O_{3}

is precipitated
(2) The blistered appearance of copper during the metallurgical process is due to evolution of

S O_{2} .

(3) Cast iron is obtained from pig iron.
(4) Hall-Heroult process is used for production of only aluminium.

Hence, the correct answer is option: 'C'.