Which one of the following is the kinetic energy of a gaseous mixture containg 3 g of hydrogen and 80 g of oxygen at temperature T(K) ?

Options

A. 3RT
B. 6RT
C. 4RT
D. 8RT

Answer

B

Explanation

`K.E=(3)/(2) n RT`
n= number of moles.
(Hydrogen) no. of moles
`=("Hydrogen mass")/("Hydrogen molar mass")`
`(3g)/(2)=1.5`.
(Oxygen)no. of moles
`=("Oxygen mass")/("Oxygen molar mass")`
`=(80g)/(32 gmol^-1)=2.5`.
`n=1.5 +2.5=4`
`K.E.=(3)/(2) n R T`.
`=(3)/(2)xx 4 RT -6RT`.