Given: V1 = Initial volume = 6.851 L
P1 = Initial pressure = 772 mm Hg, P2 = Final pressure = 760 mm Hg
T1 = Initial temperature = 35 °C = 35 + 273.15 K = 308.15 K
T2 = Final temperature = 273.15 K
To find: V2 = Final volume
Formula: \(\frac{\mathrm{P}_{1} \mathrm{~V}_{1}}{\mathrm{~T}_{1}}=\frac{\mathrm{P}_{2} \mathrm{~V}_{2}}{\mathrm{~T}_{2}}\)
Calculation: According to combined gas law,
\(\frac{P_1V_1}{T_1}=\frac{P_2V_2}{T_2}\)
\(V_2=\frac{P_1V_1T_2}{P_2T_1}=\frac{772\times6.851\times273.15}{308.15\times760}=6.169 L\)
Ans: The volume of gas at STP is 6.169 L.
