Assertion :

We add caustic alkali to bauxite ore during purification of bauxite.

Reason: Bauxite dissolves in caustic alkali and thus impurities can be separated

Q.

Assertion – The non-fusible impurities present in iron ore are removed by $CaC{O}_3$ .

Reason: $CaC{O}_3$ which decomposes into $CaO$ and $C{O}_2$. The $CaO$ formed reacts with $Si{O}_2$ to remove silica

Q. Assertion: The impurities such as ${\text{SiO}}_2$ present in iron ore is removed by ${\text{CaCO}}_3$.

Reason: $\text{CaO}$ formed by decomposition of ${\text{CaCO}}_3$ reacts with ${\text{SiO}}_2$ to form slag.

Q. Assertion: The compressibility factor for $H_2$​ and $He$ is $(1+\frac{Pb}{RT})$
Reason: The compressibility factor for $H_2$​ and $He$ can be derived from Van der Waal's equation.

Q.

Assertion (A) Order of the reaction can be zero or fractional.

Reason (R) We cannot determine order from balanced chemical equation.

(a) Both assertion and reason are correct and the reason is correct explanation of assertion
(b) Both assertion and reason are correct, but reason does not explain assertion.
(c) Assertion is correct, but reason is incorrect
(d) Both assertion and reason are incorrect
(e) Assertion is incorrect but reason is correct.

Q. Assertion : Two electrons of helium atom are placed in only one shell but three electrons of lithium need two shells.
Reason: A shell can have maximum ${\text{2n}}^2$ electrons.