Equal masses of $$\mathrm{H}_{2(\mathrm{~g})}$$ and $$\mathrm{He}_{(\mathrm{g})}$$ are enclosed in a container at constant temperature. The ratio of partial pressure of $$\mathrm{H}_2$$ to $$\mathrm{He}$$ is

What volume of $$\mathrm{CO}_{2(\mathrm{~g})}$$ at STP is obtained by complete combustion of $$6 \mathrm{~g}$$ carbon?

A hot air balloon has volume of $$2000 \mathrm{~dm}^3$$ at $$99^{\circ} \mathrm{C}$$. What is the new volume if air in balloon cools to $$80^{\circ} \mathrm{C}$$ ?

If $$\mathrm{N}_2$$ gas is compressed at 2 atmosphere from 9.0 L to $$3.0 \mathrm{~L}$$ at $$300 \mathrm{~K}$$, find the final pressure at same temperature.