Question

A mixture of helium and neon gases is collected over one liter water at 28 degrees celcius and 745 mmHg. If the partial pressure of helium is 368 mmHg, what is the partial pressure of neon? ( Vapor pressure of water at 28 degrees celcius =28.3 mmHg)

Answer 1

Explanation:

The partial pressures are additive; but to solve the problem we need 1 more parameter,

P

SVP

, the

saturated vapour pressure

, which is the

vapour pressure

of water at the given temperature.

P

SVP

=

18

⋅

m

m

⋅

H

g

at

301

⋅

K

.

From above,

P

Ne

=

P

Total

−

P

He

−

P

SVP

=

(

745

−

368

−

18

)

⋅

m

m

⋅

H

g

=

?

?

⋅

m

m

⋅

H

g

.