To determine the effect of increasing the concentrations of the reactants on the rate of reaction, we need to consider the rate law for the reaction. The rate law expresses the rate of reaction as a function of the concentrations of the reactants, raised to powers called the reaction orders.

The general form of the rate law for the reaction 2A+B→C+D can be written as:

$Rate=k[A_{m}[B_{n}$

where k is the rate constant, and $m$ and n are the reaction orders with respect to reactants $A$ and $B$, respectively.

Since the reaction orders ($m$ and $n$) are not provided, we'll assume the reaction is first-order with respect to each reactant (a common assumption unless otherwise specified). Thus, the rate law becomes:

Rate=k[A]^1 [B]^1=k[A][B]

If the concentrations of both $A$ and B are increased by three times, the new concentrations will be [A]′=3[A] and $[B]$.

Substituting these new concentrations into the rate law: New Rate=k[A]′[B]′=k(3[A])(3[B])=k3^1 [A]3^1[B]=9k[A][B]

The new rate is 9 times the original rate.

Hence, the correct answer is option c. 9 times

To determine the effect of increasing the concentrations of the reactants on the rate of reaction, we need to consider the rate law for the reaction. The rate law expresses the rate of reaction as a function of the concentrations of the reactants, raised to powers called the reaction orders.

The general form of the rate law for the reaction 2A+B→C+D can be written as:

$Rate=k[A_{m}[B_{n}$

where k is the rate constant, and $m$ and n are the reaction orders with respect to reactants $A$ and $B$, respectively.

Since the reaction orders ($m$ and $n$) are not provided, we'll assume the reaction is first-order with respect to each reactant (a common assumption unless otherwise specified). Thus, the rate law becomes:

Rate=k[A]^1 [B]^1=k[A][B]

If the concentrations of both $A$ and B are increased by three times, the new concentrations will be [A]′=3[A] and $[B]$.

Substituting these new concentrations into the rate law: New Rate=k[A]′[B]′=k(3[A])(3[B])=k3^1 [A]3^1[B]=9k[A][B]

The new rate is 9 times the original rate.

Hence, the correct answer is option c. 9 times