A gaseous mixture contains CH4 and C2H6 in the mass ratio 4 : 5. Which statements are correct?

The mole ratio CH4 : C2H6 is 3 : 2

The mole fraction of CH4 is 0.6

At a total pressure of 5 atm the partial pressure of C2H6 is 2 atm

The average molar mass of the mixture is 21.6 g mol^-1

The mole ratio CH4 : C2H6 is 3 : 2

The mole fraction of CH4 is 0.6

At a total pressure of 5 atm the partial pressure of C2H6 is 2 atm

The average molar mass of the mixture is 21.6 g mol^-1

JEE Advanced levelOne or more correct optionsDifficulty 3 of 3ig162

A gaseous mixture contains $CH X_{4}$ and $C X_{2} H X_{6}$ in the mass ratio $4 : 5$ . Which statements are correct?

AThe mole ratio $CH X_{4} : C X_{2} H X_{6}$ is $3 : 2$
BThe mole fraction of $CH X_{4}$ is $0.6$
CAt a total pressure of $5 atm$ the partial pressure of $C X_{2} H X_{6}$ is $2 atm$
DThe average molar mass of the mixture is $21.6 g mo l^{- 1}$

Take

4 g

CH X_{4}

and

5 g

C X_{2} H X_{6}

: moles

4/16 = 0.25

and

5/30 = 0.1667

, ratio

3 : 2

(A),

x_{CH X_{4}} = 0.6

(B).

p_{C X_{2} H X_{6}} = 0.4 \times 5 = 2 atm

(C).

\overset{ˉ}{M} = 0.6 \times 16 + 0.4 \times 30 = 9.6 + 12 = 21.6

(D). All correct.