Question

3.Rajiv took three substances P, Q, and R and burnt them one by one. He noted down his observations given below:
I. Substance P burns quickly producing heat and light. II. Substance Q burns in room temperature on its own.
III. Substance R burns with the evolution of heat, light, and sound. Which of the following statements regarding the given information is correct? A) Substances P and Q are undergoing rapid combustion whereas R is undergoing explosion.
B) Substances P and R are undergoing spontaneous combustion whereas Q is undergoing rapid combustion.
C) Substance P is undergoing rapid combustion, Q is undergoing spontaneous combustion while R is undergoing explosion.
D) Substance P is undergoing spontaneous combustion, Q is undergoing rapid combustion while R is undergoing explosion.

Answer 1

Answer:

The answer is c

Explanation:

Clearly option q burns on its own so it is an example of spontaneous combustion

And r is exploding because it releases heat as well as light as well as sound.

Answer 2

The correct answer is :

C) Substance P is undergoing rapid combustion, Q is undergoing spontaneous combustion while R is undergoing explosion.

• As mentioned in the question we know that specimen P burns quickly producing heat and light. The keyword here being quickly classifies it as a rapid combustion.
• The specimen Q burns in room temperature with no external influence. The keyword being no external influence classifies it as a spontaneous combustion.
• The specimen R on burning releases heat, light and sound. Usually when all three forms of energy loss is released simultaneously it is classified as an explosion.