400 ml of a gas is contained at 300 mm Hg and 0°C. What will its volume be in mL at 140 mm Hg and 10°C?

1 Answer
Mar 13, 2017

Answer:

The #"combined gas law"# holds that for a given quantity of gas.......

..........#V_2=889*mL#

Explanation:

The #"combined gas law"# holds that for a given quantity of gas.......

#(P_1V_1)/T_1=(P_2V_2)/T_2#, so we convert to absolute temperature, and solve for #V_2#.

#V_2=(P_1V_1T_2)/(T_1P_2)#.

We immediately see (do we?) that the right hand side of the equation has units of volume as required.

And so,

#V_2=(300*mm*Hgxx400*mLxx283*K)/(273*Kxx140*mm*Hg)=889*mL.#

Normally, we would have to convert the pressure measurement to a more conventional atmospheres (i.e. #760*mm*Hg-=1*atm)#, but we can forgo this step here since the pressure measurements cancel.