Question

The rate of a reaction depends upon:
(This question has multiple correct options)
(A) Temperature
(B) Concentration
(C) Catalyst
(D) Density

Answer 1

Hint: Some reactions such as ionic reactions undergo very fast. On the other hand, some reactions are very slow. Precipitation reactions and corrosion of metals are examples of such reactions respectively. Some reactions are moderate speed like the inversion of cane sugar. So, the speed of reaction or rate of reaction depends on many factors of the reaction.

Complete step by step answer:
The change in concentration of reactant or product in unit time is defined as the rate of reaction.
More specifically, the rate of reaction depends on the decreasing concentration of reactants or increasing the concentration of products.
Consider a reaction, $A\to B$
From the definition,
Rate of reaction = rate of disappearance of A/per unit time = rate of appearance of B/per unit time
The units of the rate of reaction are concentration per time. Then the units will be mol/L.s
The rate of reaction depends on the concentration of reactants, temperature, pressure (in case of gaseous reactants), and catalyst.
1. Concentration: the increasing the rate of reaction with increasing the concentration of one or more reactants. The collision of the reactants will increase in a specific period because of higher concentration.

2. Temperature: the rate of reaction increases with increasing the rate of reaction. If temperature increases, the kinetic energy of molecules increases and will have minimum energy for an effective collision.

3. Catalyst: a substance that increases the rate of a reaction without participating in a reaction is known as a catalyst, which provides an alternative path for reaction to obtain products.

4. Pressure: if increasing the pressure of reaction, no change in the rate of reaction when the reactants and products are solid or gaseous phase. But the reactants or products are in the gaseous phase, increasing the pressure, the chances of collision increase. So the rate of reaction increases.
Hence, the rate of reaction depends upon concentration, temperature, pressure, and catalyst.
So, the correct answer is “Option A, B, C , D”.

Note: The physical state of the reactants and surface area also impacts the rate of reaction. The rate of reaction will be limited by the surface area of the phases in contact, when the reactant molecule is in a heterogeneous mixture. The surface area of solid reactants will increase the reaction rate.