Gas Lews in Chemistry

Question

What pressure results when 2.65 x 10^-3 g of Cl₂(g), initially at 21.5 ˚C under a pressure of 645.3 mm Hg in a 0.606 L container, are heated to 26.8 ˚C and the volume is allowed to expand to 2,060 mL? in mmHg

Answer 1

Combined Gas Law: P1V1/T1 = P2V2/T2

P1 = initial pressure = 645.3 mm Hg

V1 = initial volume = 0.606 L

T1 = initial temperature = 21.5ºC + 273 = 294.5K

P2 = final pressure = ?

V2 = final volume = 2060 ml x 1 L / 1000 ml = 2.060 L

T2 = final temperature = 26.8ºC + 273 = 299.8K

Solving for P2, we have ...

P2 = P1V1T2 / V2T1

P2 = (645.3)(0.606)(299.8) / (2.060)(294.5)

P2 = 193 mm Hg

If you want the final pressure in atm, simply divide by 760