The pressure of a gas in a vessel is 80 cm of Hg. Now 25% of the same gas is also introduced into the same vessel. If the process is done at the same temperature, find the final pressure of the gas.

The pressure of a gas in a vessel is 80 cm of Hg. Now 25% of the same

1.	The pressure of a gas in a vessel is 80 cm of Hg. Now 25% of the same gas is also introduced into the same vessel. If the process is done at the same temperature, find the final pressure of the gas.
Answer» <P> Solution : Initial pressure of gas `(P_(1) )`=80 cm of Hg Initial mass of the gas `(m_(1))`= m Final mass of the gas `(m_(2)) = m + (m)/(4) = (5M)/(4)` Final pressure of the gas `(P_(2)) = ? ` At constant volume and TEMPERATURE , According to ideal gas equation , `(P_(1))/(m_(1)) = (P_(2))/(m_(2))` `RARR P_(2) = (m_(2))/(m_(1)) P_(1) = (5 m//4)/(m) xx 80` `= (5)/(4) xx 80 = 100 " cm of Hg, " therefore P_(2) = 100` cm of Hg