Question

Give the unit rate of reaction
A.Molar
B.Second
C.Second/molar
D.Molar/second

Answer 1

The speed of a chemical reaction is the change of a substance in a time interval in which the change happens.

Complete step by step answer:
It is the change in the concentration in a given time interval. By changing the concentration of the substance taking part in the reaction usually changes the rate of reaction.
So that means, the unit of reaction rate is $\Delta$ Concentration/ $\Delta$ Time. This is most often M/S, where M is molarity (Moles per litre) and the S is the time in seconds. So, the unit rate reaction i.e., the change of substance that happens in one second.
So, the unit rate of reaction is Molar/Second.

Therefore, the correct answer is option (D).

Note: The rate of reaction r(t) in a rate law is given as
$r(t) = k{[A]^m}{[B]^n} = \dfrac{1}{a}\dfrac{{\Delta [A]}}{{\Delta t}} = - \dfrac{1}{b}\dfrac{{\Delta [B]}}{{\Delta t}} = \dfrac{1}{c}\dfrac{{\Delta [C]}}{{\Delta t}} = \dfrac{1}{d}\dfrac{{\Delta [D]}}{{\Delta t}}$ for the reaction aA + bB $\to$ cC + dD
Where, k is the rate constant, [] is the concentration of the given reactant.
The change of chemical that occurs in unit time is unit rate reaction.