Question

Aliya is making hot chocolate by adding cocoa powder to hot water. She notices that the cocoa powder dissolves very quickly when she adds it to hot water as compared to cold water without much stirring. Why do you think this happens?

A: The cold temperature and small size of particles increase the rate of dissolving.
B: The hot temperature and color of the powder increase the rate of dissolving.
C: The hot water and large size of particles increase the rate of dissolving.
D: The hot water and small size of particles increase the rate of dissolving.

Answer 1

D

Step-by-step explanation:

self-explanatory:

higher temperature increases rate of dissolving

smaller particles means a larger surface area,therefore increasing rate of dissolving as more of the solute is in contact with the solvent at one time.