Question

Which of the following temperature changes would decrease the volume of a sample of gas?

Group of answer choices

0C to 10C

300K to 400K

20C to 10C

no correct response

If the pressure pm 30.0 mL of a gas is changed from 1.00 atm to 2.00 atm the new volume, in mL, will be

Group of answer choices

15.0 mL

32.0 mL

60.0 mL

no correct response

Answer 1

Here is the complete solution. Please mention any query in the comment section regarding the question.

Solution:

1. We know that volume of a gas is directly proportional to temperature (Charles' law) So, increase in volume will result in increase in temperature and vice versa.

In the given question we need to find the option for the temperature change due to which volume of the gas will decrease. Now, since we know that increase in temperature will increase in volume and decrease in temperature will decrease in volume. So, in the given options only option (C) is the option where there is decrease in temperature (i.e. from 20C to 10C). So this will result in decrease in volume.

2. In this question a certain volume (V₁ = 30 mL) of gas at pressure (P₁ = 1 atm) has gone through a change in pressure to P₂ = 2 atm and we are asked to find out the change in volume.

Now, we know that PV = nRT ( ideal gas equation). In the given condition the only thing that has changed is pressure, so we can write

PV = Constant or    P₁V₁ = P₂V₂ (so we have to find out the final volume V₂)

=> 1 x 30 = 2 x V₂

=> V₂ = 30/2 = 15 mL

So the correct option is option (a) V₂ = 15 mL