Vulcanization of rubber is carried out by heating a mixture of

Animal starch is the other name of

Given below are two statements: one is labelled as Assertion $$\mathbf{A}$$ and the other is labelled as Reason $$\mathbf{R}$$.

Assertion A: Phenolphthalein is a $$\mathrm{pH}$$ dependent indicator, remains colourless in acidic solution and gives pink colour in basic medium.

Reason R: Phenolphthalein is a weak acid. It doesn't dissociate in basic medium.

In the light of the above statements, choose the most appropriate answer from the options given below.

A $$10 \mathrm{~g}$$ mixture of hydrogen and helium is contained in a vessel of capacity $$0.0125 \mathrm{~m}^{3}$$ at 6 bar and $$27^{\circ} \mathrm{C}$$. The mass of helium in the mixture is ____________ g. (nearest integer)

Given: $$\mathrm{R}=8.3 \mathrm{~J} \mathrm{~K}^{-1} \mathrm{~mol}^{-1}$$

(Atomic masses of $$\mathrm{H}$$ and $$\mathrm{He}$$ are $$1 \mathrm{u}$$ and $$4 \mathrm{u}$$, respectively)