The macromolecular colloids of the following are

I. Starch solution

II. Sulphur sol

III. Synthetic detergent

IV. Synthetic rubber

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