Question

Assertion (A): All exothermic reactions are accompanied with evolution of heat and light.
Reason (R): Combination reactions may or may not be exothermic.
In the light of the above statements, choose the most appropriate answer from the options given below:

• A. Both Assertion (A) and Reason (R) are true, and Reason (R) is the correct explanation of Assertion (A).
• B. Both Assertion (A) and Reason (R) are true, and Reason (R) is not the correct explanation of Assertion (A).
• C. Assertion (A) is true, but Reason (R) is false.
• D. Assertion (A) is false, but Reason (R) is true.

Hint:

In an exothermic reaction, energy is released in the form of heat and light, but this is not the case for all reactions.

Answer 1

The Correct Option is D

Assertion (A) is false because not all exothermic reactions release both heat and light. Some exothermic reactions only release heat. 
Reason (R) is true because combination reactions may or may not be exothermic, depending on the specific reaction conditions. 
Therefore, the correct answer is option (4).