Question

The volume of a gas is 200mL at 2.0atm. What will it's volume be at 4.0atm?​

Answer 1

The new pressure will be

1000 L

, rounded to one significant figure.

Explanation:

Boyle's law states that when a gas is held at a constant temperature and mass in a closed container, the volume and pressure vary inversely. The equation to use is

P

1

V

1

=

P

2

V

2

.

Given

V

1

=

200

mL

×

1

L

1000

mL

=

0.2 L

P

1

=

700 mmHg

V

2

=

100

mL

×

1

L

1000

mL

=

0.1 L

Unknown

P

2

Equation

P

1

V

1

=

P

2

V

2

Solution

Rearrange the equation to isolate

P

2

and solve.

P

2

=

P

1

V

1

V

2

P

2

=

(

700

mmHg

×

0.2

L

)

0.1

L

=

1400 L

, which must be rounded to

1000 L

because all of the measurements have only one significant figure

Answer 2

Answer:

V = 100 ml

Explanation:

P1V1 = P2V2

P1 = 2.0 atm

V1 = 200ml

P2 = 4.0 atm

V2 = ?

(2.0)(200) = (4.0)V2

400 = (4.0)V2

V2 = 100