Chemistry MCQ Practice

Benzoic acid is widely used in the food industry as a food preservative. The melting and boiling points of benzoic acid are 122 °C and 249 °C respectively.

 

Which of the following will occur to the particles of benzoic acid when it is cooled from 400 °C to 100 °C?

 

	distance between particles	energy of particles
A)	decreases	decreases
B)	decreases	increases
C)	increases	decreases
D)	increases	increases

 

 

Answer: A

 

In this question, the melting and boiling points given are redundant. The key concept here is that the substance is cooled.

 

For any substance that is cooled, the distance between particles will decrease and the energy of particles will decrease.

 

Similarly for any substance that is heated, the distance between particles will increase and the energy of particles will increase.