Assertion :Primary succession occurs in a freshly harvested field. Reason: Succession occurs over a bare area.

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: n-Pentane and n-Hexane belong to a homologous series.

REASON: n-Pentane and n-Hexane belong to the same class of hydrocarbons and they differ by a - $C{H}_2$ - group.

Q. Regarding the given assertion and reason, choose the right option

Assertion [A]: Primary succession occurs in a freshly harvested field.
Reason [R]: Successsion always occurs over a bare area.

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. Choose the correct option for the given assertion and reason.
Assertion: Two plane mirrors kept at right angle deviate any ray of light by ${180}^{\circ }$ after two successive reflections.
Reason: The above condition is satisfied only for angle of incidence, $i={45}^{\circ }$.