Answer:
2nd order reaction
Explanation:
Let us assume the reaction to be:
R → P
Where R is the reactant and P is the product.
So here, say initially we have "a" amount of reactant.
R → P
At t=0: a 0 (initial condition)
At t=t: a-x x
Say x be the amount of reactant which forms the product in time t.
So from the rate law, we have
rate of decomposition = k (R)ⁿ
Where k is rate constant , R is amount of reactant at time t and n is the order of the reaction
From the question, at the instant when 5% and 20% have reacted, we will be left with 95% and 80% of the reactant respectively. So writing the rate law equation:
1.07 = k ( 95a / 100)ⁿ
0.76 = k ( 80a/100)ⁿ
Dividing these two equations, we get:
(1.07 / 0.76 ) = ( 95/80 )ⁿ
Taking logarithm on both sides we get
n = ( ㏒ (1.07 / 0.76) ) ÷ ㏒(95/80) = 2.0067 ≈ 2
Therefore the reaction is of order 2