Question

question 24
a mixture of 10.0 g of ne and 10.0 g of ar have a total pressure of 1.6 atm. what is the partial pressure of ne?
1.10 atm
0.54 atm
0.80 atm
0.66 atm

Explanation:

Step1: Calculate moles of Ne and Ar

Molar mass of Ne is \(20.18\space g/mol\), moles of Ne: \(n_{Ne}=\frac{10.0\space g}{20.18\space g/mol}\approx0.4955\space mol\)
Molar mass of Ar is \(39.95\space g/mol\), moles of Ar: \(n_{Ar}=\frac{10.0\space g}{39.95\space g/mol}\approx0.2503\space mol\)

Step2: Find mole fraction of Ne

Total moles: \(n_{total}=n_{Ne}+n_{Ar}=0.4955 + 0.2503 = 0.7458\space mol\)
Mole fraction of Ne: \(X_{Ne}=\frac{n_{Ne}}{n_{total}}=\frac{0.4955}{0.7458}\approx0.664\)

Step3: Calculate partial pressure of Ne

Using Dalton's law: \(P_{Ne}=X_{Ne}\times P_{total}\)
\(P_{Ne}=0.664\times1.6\space atm\approx1.06\space atm\) (closest to 1.10 atm)

Answer:

1.10 atm (the option with "1.10 atm")