A gas syringe at 20°C contains 20.0 mL of CO2 gas. The pressure of the gas in the syringe is 1.0 atm. What is the pressure in the syringe at 20°C if the plunger is depressed to 10.0 mL?

2atm

Explanation:

Data obtained from the question include:

T1 = 20°C = 20 +273 = 293K

V1 = 20.0 mL

P1 = 1atm

T2 = 20°C = 20 +273 = 293K

V2 = 10mL

P2 =?

From the above, we observed that the temperature is constant. Therefore the gas is obeying Boyle's law. The new pressure can be obtain by using P1V1 =P2V2 as shown below:

P1V1 =P2V2

1 x 20 = P2 x 10

Divide both side by 10

P2 = 20/10

P2 = 2atm

Therefore, the new pressure is 2atm.

The new pressure is 2.0 atm

Explanation:

Step 1: Data given

Temperature = 20.0 °C = 293 K

Volume = 20.0 mL = 0.02 L

The pressure = 1.0 atm

The volume decreases to 10.0 mL = 0.01 L

The temperature stays constant at 293 K

Step 2: Calculate the new pressure

P1*V1 = P2*V2

⇒with P1 = the initial pressure = 1.0 atm

⇒with V1 = the initial volume = 0.02 L

⇒with P2 = the final pressure = TO BE DETERMINED

⇒with V2 = the final volume = 0.01 L

1*0.02 = P2 * 0.01

P2 = 0.02/0.01

P2 = 2.0 atm

The new pressure is 2.0 atm