Answer : The correct option is, (C) 120 L
Explanation :
Combined gas law is the combination of Boyle's law, Charles's law and Gay-Lussac's law.
The combined gas equation is,
\(\frac{P_1V_1}{T_1}=\frac{P_2V_2}{T_2}\)
where,
\(P_1\) = initial pressure of gas = 0.50 atm
\(P_2\) = final pressure of gas = 1.2 atm
\(V_1\) = initial volume of gas = ?
\(V_2\) = final volume of gas = 48 L
\(T_1\) = initial temperature of gas = 325 K
\(T_2\) = final temperature of gas = 320 K
Now put all the given values in the above equation, we get:
\(\frac{0.50atm\times V}{325K}=\frac{1.2atm\times 48L}{320K}\)
\(V_1=117L\approx 120L\)
Therefore, the initial volume was 120 L.
