Question

A sealed bottle is full of air. The volume of the bottle is decreased, but the temperature remains constant. What other change occurs in the bottle?

A.
The air pressure will increase.
B.
The air pressure will decrease.
C.
The number of air molecules will increase.
D.
The number of air molecules will decrease.

Answer 1

I believe A is the answer

Answer 2

Hello!

The other change that will occur in the bottle is that A. The air pressure will increase.

Why?

If volume changes in a closed container, while temeprature remains constant, the phenomenon is described by Boyle's Law:

$P1*V1=P2*V2$

Let's give some arbitrary values to these variables:

P1= 1 atm

V1= 2 L

P2= ?

V2= 1 L

Calculating the final pressure (P2):

$P2=\frac{P1*V1}{V2}=\frac{1 atm*2 L}{1 L}=2 atm$

So, the final pressure is higher than the initial pressure (P2>P1). That means that Pressure and Volume are inversely proportional.

Have a nice day!