Two solutions of `A` and`B` are available. The first is known to contain `1` mole of `A` and `3` moles of `B` and its total vapour pressure is `1.0` atm. The second is known to contain `2` moles of `A` and `2` moles of `B`, its vapour pressure is greater than `1` atm, but if is found that this total vapour pressure may be reduced to `1` atm by the addition of `6` moles of `C`. The vapour pressure of pure `C` is `0.80` atm. Assuming ideal solutions and that all these data refered to `25^(@)C`, calculate the vapour pressure of pure `A` and `B`.

Answer

`P_(B)^(0)=0.7` atm and `P_(A)^(0)=1.9` atm.

Explanation

The data provide the following two expressions for total pressure
`1=(1)/(4)P_(A)^(0)+3P_(B)^(0)`
or `4=P_(A^(0))+3P_(B^(0))` and `1=(1)/(5)P_(A)^(0)+(1)/(5)P_(B)^(0)+(3)/(5)P_(C)^(0)`
or `4=P_(A)^(0)+P_(B)^(0)+2.4`
on solving these two equations simultaneously. one obtains `P_(B)^(0)=0.7` atm and `P_(A)^(0)=1.9` atm.