Question

Physical Science Gas Laws Test

Answer 1

1. A gas occupies 4.31 litres at a pressure of 0.755atm. Determine the volume if the pressure is increased to 1.25 atm.

method: Boyles Law: P1/V1 = P2/V2
P1/V1 = P2/V2 implies V2= P2 V1/ P1
V2=1.25x4.31 / 17=7.13L


2. 600 mL of a gas is at a pressure of 8.00atm. What is the Volume of the gas at 2 atm?

method: Boyles Law: P1/V1 = P2/V2
P1/V1 = P2/V2 implies V2= P2 V1/ P1,
V1=2.6mL=0.026L
V2= P2 V1/ P1= 0.00065 L

3. How hot will a 2.3 L balloon have to get to expand to a volume of 400 L? Assume that the initial temperature of the balloon is 25 degrees Celsius.

Method: Charles Law: V1/T1 =V2/T2  Degrees Celcius + 273 = Kelvin

25 degrees Celsius=25+273=298K=T1

V1=2.3L, V2=400L

V1/T1 =V2/T2 implies T2=V2T1/V1=(400x298) /2.3=51826 K

4. A gas takes up a volume of 17 litres, has a pressure of 2.3atm, and a temperature of 299K. If I raise the temperature to 350K and lower the pressure to 1.5atm, what is the new volume of the gas?

Combined gas Law: (P1)(V1) =  (P2)(V2)
                                     (T1)           (T2)

V1=17L
P1=2.3 atm
T1= 299K
P2=1.5 atm
T2=350 K
V2=?

 (P1)(V1) / T1=  (P2)(V2)/ T2
                                 
so V2= (P1)(V1) T2 / P2 T1
V2=17x2.3x350 /1.5 x 299= 30.51L