Question

A mixture of He and Ne at a total pressure of 0.95 atm is found to contain 0.32 mol of He and 0.56 mol of Ne. The partial pressure of Ne is ________ atm.
(A) 1.7
(B) 1.5
(C) 0.60
(D) 0.35
(E) 1.0

Answer 1

Answer:

Partial pressure of Ne is 0.61 atm

Explanation:

Let's assume mixture of He and Ne behaves ideally.

Then, according to Dalton's law for partial pressure in a mixture of gas-

                                      $P_{gas}=x_{gas}.P_{total}$

Where $P_{gas}$ is partial pressure of a gas in mixture, $x_{gas}$ is mole fraction of a gas in mixture and $P_{total}$ is total pressure of mixture.

Here, $x_{Ne}$ = (number of moles of Ne)/(Total number of moles in mixture)

So, $x_{Ne}$ = $\frac{0.56}{0.56+0.32}=0.64$

So,  $P_{Ne}=x_{Ne}.P_{total}$ = $(0.64\times 0.95 atm)=0.61atm$

Answer 2

Answer:

The answer is C- 0.60

Explanation:

Here, x_{Ne} = (number of moles of Ne)/(Total number of moles in mixture)

So, x_{Ne} = \frac{0.56}{0.56+0.32}=0.64

So, P_{Ne}=x_{Ne}.P_{total} = (0.64\times 0.95 atm)=0.601atm