The equilibrium constant (`K_c`) for the following equilibrium `2So_(2(g)) + O_(2(g)) iff 2SO_(3(g))` at 563K is 100. at equilbrium, the number of moles of `SO_3` in the 10 litre flask is twice the number of moles of `SO_2`, then the numbers of moles of oxygen is

Options

A. `0 . 4`
B. `0 . 3`
C. `0 . 2`
D. `0 . 1`

Answer

A

Explanation

Let, number of moles of oxygen = x
According to equilibrium relation .
`SO_(2) (g) +O_(2) (g) hArr 2SO_(3) (g)`
`2 [ (x)/(10)][(x)/(10)]2.[(2x)/(10)]`
At equilibrium
`K_((aq))= ([(2x)/(10)]^(2))/([(x)/(10)]^(2)xx[(x)/(10)])=(4x^(2) xx 10)/(x^(2) xx x)`
`100 = (40)/(x)`
or 100 x = 40
` x = (40)/(100) = 0 . 4`
Hence, number of moles of oxygen = 0 . 4