In a catalyst experiment involving the Haber process `N_(2) + 3H_(2) rarr 2NH_(3)`, the rate of reaction was measured as
Rate `= (Delta[NH_(3)])/(Delta t) = 2.0 xx 10^(-4) mol L^(-1) s^(-1)`
What is the rate of reaction expressed in terms of (a) `N_(2)` (b) `H_(2)` ?

Explanation

`N_(2)+3H_(2) rarr 2NH_(3)`
`(-d[N_(2)])/(d t) = (-d[H_(2)])/(3 d t) = (+d[NH_(3)])/(2 d t)`
(a) `:. (-d[N_(2)])/(d t) = (1)/(2) xx (d[NH_(3)])/(d t) = (1)/(2) xx 2.0 xx 10^(-4)`
`= 10^(-4) mol L^(-1) s^(-1)`
(b) `(-d[H_(2)])/(d t) = (3)/(2) xx (d[NH_(3)])/(d t)`
`= (3)/(2) xx 2.0 xx 10^(-4) = 3 xx 10^(-4) mol L^(-1) s^(-1)`