Equal moles of hydrogen and oxygen gases are placed in container with a pin-hole through which both can escape. What fraction of the oxygen escapes in the time required for one-half of the hydrogen to escape?
1. 1/4
2. 3/8
3. 1/2
4. 1/8
If van der Waals constant "a" for NH3, H2 and CO2 are respectively 4.17, 0.244, 1.36 and 3.59, then which one of the following gases is most easily liquefied?