Phase, state and components

Q. At ${48}^{o}C$, the vapour pressure of pure $C{S}_2$ in $850\text{torr}$. A solution of $2.0\text{g}$ of sulphur in $100\text{g}$ of $C{S}_2$ has a vapour pressure $844.9\text{torr}$. Determine the atomicity of sulphur molecule.

1. $16$
2. $8$
3. $4$
4. $10$

Q.

The detergent action of soap is due to its

1. Solubility in water

2. Ability to produce lather

3. Acidity

4. Emulsifying property