Question

What is a catalyst?
a.) A substance that changes the rate of a chemical reaction without being consumed in the reaction.
b.) A substance that changes the product of a chemical reaction and is consumed in the reaction.
c.) A substance that changes the product of a chemical reaction without being consumed in the reaction.
d.) A substance that changes the reactants of a chemical reaction without being consumed in the reaction.
e.) A substance that changes the rate of a chemical reaction and is consumed in the reaction.

Answer 1

Hint: In chemistry the rate of reaction is also a very important aspect. Do you know, some of the reactions can take hundreds, even thousands, of years to finally finish and give products while some take less than a second. In these cases what can we do to properly observe the reaction?

Complete step by step solution:

Let’s first see what happens when a reaction occurs and then we will define what is the rate of reaction and catalysts.
In the process of chemical reaction, molecules break chemical bonds between their atoms. The atoms also make new bonds with different atoms and new molecules. This leads to the formation of products (new molecules) from the reactants (older molecules).
Rate of reaction is defined as the speed at which a chemical reaction happens. In other words, it is the speed at which the products are formed from the reactants in a chemical reaction i.e. if the rate of reaction is low, the molecules break or combine at a slower speed and if it is high the molecules break or combine at a high rate. There are various factors which affect the rate of reaction, catalyst is also one of them.
Catalysts are a substance that alters the rate of reaction, and allows the reaction to attainment equilibrium quickly. The catalyst just changes the path of the reaction by reducing the activation energy, so the reaction happens more efficiently. It also doesn’t get consumed in the reaction. Catalysts can be used in any form either solid, liquid or gas.
So, the correct option is (a).

Note: We should also know that there is something called an inhibitor also. It works exactly the opposite way as compared to catalysts. Inhibitors slow down the rate of reaction or sometimes they even completely stop the reaction.