Assertion Reasoning is one of the most important types of questions in science subjects like Physics, Chemistry, and Biology, especially in exams like CBSE Class 10, 11, 12 and competitive exams like NEET, JEE, CUET, etc. If we understand the meaning of both “assertion” and “reasoning,” it becomes easy to solve such questions. Let’s go step-by-step in simple words to learn how to solve assertion reasoning questions correctly.
What is Assertion?
In simple language, an Assertion is a statement that says something is true. It is like a sentence which tells a fact, concept or conclusion. This statement is usually related to a scientific rule or observation.
Example:
- Assertion: Water boils at 100°C at normal atmospheric pressure.
Here, the statement is a fact. So, this is an assertion.
What is Reason?
A Reason is a second statement which tries to explain why the assertion is true. It supports the assertion if the explanation is correct.
Example:
- Reason: Because boiling point of water depends on atmospheric pressure.
This statement explains the first one. If it is correct and also related to assertion, then both are correct and reason explains the assertion.
Format of Assertion Reasoning Questions
Generally, these questions are given in the following format:
Assertion (A): Statement 1
Reason (R): Statement 2
Then you have to choose the correct option from:
- A and R both are true, and R is the correct explanation of A.
- A and R both are true, but R is not the correct explanation of A.
- A is true but R is false.
- A is false but R is true.
How to Solve Assertion Reasoning Questions (Step-by-Step)
To solve these questions properly, follow the steps below:
- Read the assertion carefully.
See if the statement is true or false by recalling your concept or NCERT theory. - Read the reason carefully.
Again, check whether it is a correct statement on its own. - Check the relation between assertion and reason.
See whether the reason is the actual cause or explanation of the assertion. - Choose the correct option from 1 to 4 based on the analysis above.
Examples of Assertion Reasoning Questions
Example 1:
Assertion: Plants make food by photosynthesis.
Reason: Chlorophyll helps to trap sunlight.
- A is true – Yes, plants make food by photosynthesis.
- R is true – Yes, chlorophyll helps to trap sunlight.
- Does R explain A? – Yes.
Correct Answer: Option 1
Example 2:
Assertion: Sound can travel through vacuum.
Reason: Vacuum contains air particles.
- A is false – Sound cannot travel through vacuum.
- R is also false – Vacuum does not contain air particles.
Correct Answer: Option 4
Example 3:
Assertion: Boiling point of water decreases at higher altitudes.
Reason: At higher altitudes, atmospheric pressure is lower.
- A is true – Yes.
- R is true – Yes.
- Does R explain A? – Yes, less pressure means water boils at lower temperature.
Correct Answer: Option 1
Tips to Solve Assertion Reasoning Questions Easily
- Focus on keywords like “because”, “so”, “due to”.
These help to identify if R explains A. - Revise NCERT line by line.
Most Assertion Reason questions are directly based on NCERT textbooks. - Practice with examples and past questions.
Solving previous year papers improves speed and confidence. - Don’t get confused if both statements look correct.
Always check if reason actually supports the assertion or is just a true fact.
This type of question is very scoring if your concepts are clear. So just follow the steps, understand both statements separately, and then decide the correct relation between them. Keep practicing more such questions to master the skill!