A mixture of methane and ethene in a molar ratio of x:y has an average molecular mass of 20 u . The mean molar mass when they are mixed in the molar ratio of y:x will be -

Question

A mixture of methane and ethene in a molar ratio of x:y has an average molecular mass of 20 u . The mean molar mass when they are mixed in the molar ratio of y:x will be - (A) 20 u (B) 25 u (C) 24 u (D) 15 u

Tardigrade Admin · Accepted Answer

Mol. wt. of CH4=16 Mol. wt. of C2H4=28 ∴ 20=(16 x + 28 y/x + y) or 16x+28 y=20 x+20 y or 4x=8y or x=2y In the gaseous mixture when the mole ratio of CH4 and C2H4 is y:x then avg. mol. wt=(16 y + 28 x/x + y)=(16 y + 56 y/3 y) =(72 y/3 y)=24 u

Q. A mixture of methane and ethene in a molar ratio of $x : y$ has an average molecular mass of $20 u$ . The mean molar mass when they are mixed in the molar ratio of $y : x$ will be -

$20 u$

$25 u$

$24 u$

$15 u$

Q. A mixture of methane and ethene in a molar ratio of x:y has an average molecular mass of 20u . The mean molar mass when they are mixed in the molar ratio of y:x will be -

20u

25u

24u

15u

Mol. wt. of CH4​=16 Mol. wt. of C2​H4​=28 ∴20=x+y16x+28y​ or 16x+28y=20x+20y or 4x=8y or x=2y In the gaseous mixture when the mole ratio of CH4​ and C2​H4​ is y:x then avg.mol.wt=x+y16y+28x​=3y16y+56y​ =3y72y​=24u

Q. A mixture of methane and ethene in a molar ratio of $x : y$ has an average molecular mass of $20 u$ . The mean molar mass when they are mixed in the molar ratio of $y : x$ will be -

$20 u$

$25 u$

$24 u$

$15 u$