what is law of mass action??

Dear sachin,

Guldberg and Waage showed that for a reaction aA + bB → cC + dD,
the rate (speed) of the reaction in either direction is proportional to what they called the "active masses" of the various components:

rate of forward reaction = k_f [A]^a [B]^b

rate of reverse reaction = k_r [C]^c [D]^d

in which the proportionality constants k are called rate constants and the quantities in square brackets represent concentrations. If we combine the two reactants A and B, the forward reaction starts immediately; then, as the products C and D begin to build up, the reverse process gets underway. As the reaction proceeds, the rate of the forward reaction diminishes while that of the reverse reaction increases. Eventually the two processes are proceeding at the same rate, and the reaction is at equilibrium:

rate of forward reaction = rate of reverse reaction

k_f [A]^a [B]^b = k_r [C]^c [D]^d

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All the best.

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