Question

The rate law for the single step reaction \[2A + B \to 2C\] , is given by:
 A.$rate = k[A][B]$
B. $rate = k{[A]^2}[B]$
C. $rate = k[2A][B]$
D. $rate = k{[A]^2}{[B]^0}$

Answer 1

Hint: Basically, the rate of reaction refers to the speed at which the products are formed from the reactants in a chemical reaction. Moreover, there are various rate laws that govern the rate of a reaction. So, to solve this question we need to know the general rate law equation.

Complete step by step answer:
When we talk about chemical reactions, we know that some chemical reactions are nearly instantaneous while others usually take some time to reach the final equilibrium. Now, the rate law also known as the rate equation for a chemical reaction is an expression which provides a relationship between the rate of the reaction and the concentration of the reactants that are participating in it.
Now, let’s determine the rate of the reaction. Say for example we have been given a reaction $aA + bB \to cC + dD$ where a, b, c are coefficients of the reactants or products. Therefore, the rate of reaction is given by:
 $\Rightarrow$$Rate\alpha {[A]^X}{[B]^Y}$
 $ \Rightarrow Rate = k{[A]^X}{[B]^Y}$
 Here,[A] and [B] are the concentrations of the reactants A and B, K is the proportionality constant and X and Y are the partial reaction orders for the reactants A and B.
Now, in the given question we have to find the rate law for the single step reaction i.e. \[2A + B \to 2C\] . So, the rate law is given by:
 $\Rightarrow$ $rate = k{[A]^2}[B]$

Hence, option B is correct.

Note:
The rate of reaction depends on various factors. Some of the factors are nature of the reaction i.e. the physical state of the reactants, number of reactants etc. pressure factor i.e. the pressure increases the concentration of gases which in turn results in the increase of the rate of reaction and the last one is concentration.