Calculate the final volume when 2 moles of an ideal gas expand from $$3 \mathrm{~dm}^3$$ at constant external pressure 1.6 bar and the work done in the process is $$800 \mathrm{~J}$$.

Calculate the molar mass of an element with density $$2.7 \mathrm{~g} \mathrm{~cm}^{-3}$$ that forms fcc structure. $$\left[\mathrm{a}^3 \cdot \mathrm{N}_{\mathrm{A}}=40 \mathrm{~cm}^3 \mathrm{~mol}^{-1}\right]$$

Identify ketone from the following.

A group consists of 8 boys and 5 girls, then the number of committees of 5 persons that can be formed, if committee consists of at least 2 girls and at most 2 boys, are