Question

A vessel has nitrogen gas and water vapours are at total pressure 1atm. The partial pressure of water vapours is 0.3 atm. The contents of this vessel are transferred to another vessel having one third of capacity of original volume, completely at the same temperature the what is total pressure of the system in new vessel

Answer 1

Dear Student,

initial total pressure P= 1 atm.
partial pressure of N₂=0.3 atm
​Initial temperature= Final temperature= T
​Final Volume = $\frac{V_1}{3}$

​
According to dalton's law of partial pressure
$$\begin{gathered} P_1=p_{N_2}+p_{H_{2}O} \\ {p}_{H_{2}O}=molefraction\times Totalpressure \end{gathered}$$
$p_{N_2}=1-0.3=0.7atm$
New partial presssure of N₂ gas
p_N2V₁=( P_N2V_{2)new
$0.7\times V_1=P_{N2}\times \frac{V_1}{3}$}
(p_N2)new= 2.1 atm
Partial pressure of water vapour reamains constant at constant temperature So p_H2O​= 0.3 atm
So the total pressure in new vessel = 2.4 atm
Regards!