A cylinder contains accetylene gas at `27^(@)C` and `4.05M pa`. The pressure in the cylinder after half the mass of gas is used up and temperature has fallen to `12^(@)C` will be:

Options

A. `4.05 MP a`
B. `2.025 MP a`
C. `3.84 MP a`
D. `1.92 MP a`

Answer

D

Explanation

`PV=(w)/(M_(w))RT " " (P)/(WT)="constant"`
`(P_(1))/(w_(1)T_(1))=(P_(2))/(w_(2)T_(2)) " " (4.05)/(wxx300)=(P_(2))/((w)/(2)xx285)`
`P_(2)= 1.92MPa`