Asample of hydrogen exerts a pressure of 0.329 atm at 47 c. what will the pressure be at 77 c, assuming constant volume ?

P

2

=

0.360

a

t

m

Explanation:

Assuming that Hydrogen is behaving ideally, therefore, we can use the ideal gas law:

P

V

=

n

R

T

Since the gas is being heated only and the volume is not changing, therefore, n and V are constant and therefore we can say:

P

T

=

k

where  

k

=

n

R

V

is a constant value that does not change during the process.

Thus,  

P

1

T

1

=

P

2

T

2

This is called Gay-Lussac law.

⇒

P

2

=

P

1

T

1

×

T

2

⇒

P

2

=

0.329

a

t

m

320

K

×

350

K

=

0.360

a

t

m

the product of the pressure and volume is also constant