The equilibrium constant for the reaction `N_(2)(g) + O_(2) hArr 2NO(g) is 4 xx 10^(-4) at 2000 K.` In presence of a catalyst the equilibrium is attained ten times faster. Therefore the equilibrium constant in presence of catalyst at 2000 K is

Options

A. `40 xx 10^(-4)`
B. `4 xx 10^(-2)`
C. `4 xx 10^(-3)`
D. `4 xx 10^(-4)`

Answer

D

Explanation

` K = ("[conc. of product]")/("[conc. of reactant]")=4 xx 10^(-4)`
On adding catalyst, the equilibrium attain 10 time factor. As equilibrium constant depends on temperature. It will not change, however the reaction attains equilibrium 10 times faster hence
`K_("(new)") + K_("(previous)") = 4 xx 10^(-4)`