Assertion (A) Animal skins are colloidal in nature.

Reason (R) Animal skin has positively charged particles.

The diameters range of colloidal particles is approximately.

In an adsorption experiment, a graph between $$\log (x / m)$$ versus $$\log p$$ was found to be linear with a slope of $$45^{\circ}$$. The intercept on $$\log (x / m)$$ axis was found to be 0.3010. The amount of gas adsorbed per gram of charcoal under a pressure of $$0.5 \mathrm{~atm}$$ is

Among the following, in which type of chromatography, both stationary and mobile phases are in liquid state?