Chemistry - General Principles and Processes of Isolation of Metals Question with Solution | TestHub

(1) During leaching when bauxite is treated with concentrated NaOH, then sodium aluminate and sodium silicate is formed in the soluble form, whereas${\mathrm{F}\mathrm{e}}_2{\mathrm{O}}_3$is precipitated.

(2) The blistered appearance of copper during the metallurgical process is due to the evoluation of${\mathrm{S}\mathrm{O}}_2$.

$\text{C}{\text{u}}_2\mathrm{S}+\text{2C}{\text{u}}_2\mathrm{O}\to \text{6Cu}+\text{S}{\text{O}}_2$

(3) Cast iron is obtained from pig iron

$\underset{4\mathrm{\%}}{\text{Pig iron}}\mathrm{ }\underset{\text{air }}{\stackrel{\text{blast of }}{\to }}\underset{\text{3\%}}{\text{cast iron}}$

(4) Hall-Heroult process is used for production of only aluminium.