For the reaction R → P, the concentration of a reactant changes from 0.03M to 0.02M in 25 minutes. Calculate the average rate of reaction using units of time both in minutes and seconds.
Given-
Initial concentration(R1) = 0.03M
Final concentration(R2) = 0.02M
Time = 25 mins.
The formula for average rate of the reaction is,
→ Equation 1
∵ {R} = (R2)-( R1), the equation 1 is written as,
= 4 × 10-4 mol L-1 min-1
The average rate of reaction in seconds is given by,
= 
(dividing by 60 to convert minutes to seconds)
= 6.6 × 10-6 mol L-1 s-1
The average rate of the reaction in minutes is 4 × 10-4 mol L-1 min-1 and in seconds is 6.6 × 10-6 mol L-1 s-1
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