Arjun placed a salt cube in a cup of water. He wonders whether stirring the water will make the salt cube
dissolve faster or slower. If Arjun stirs his cup of water, what effect does it have on the rate at which the
salt cube dissolves?
A. The rate that the salt cube dissolves will speed up.
B. The rate that the salt cube dissolves will slow down.
C. The rate that the salt cube dissolves will remain the same.
D. The rate that the salt cube dissolves will slow down and then stop
The effect of stirring on the rate at which a salt cube dissolves can be understood by considering the process of dissolution. When a salt cube is placed in a cup of water, the water molecules surround the salt ions, causing them to separate from the solid cube and enter the solution. This process continues until all the salt ions have dissolved.
Stirring the water has a significant effect on the rate of dissolution. When you stir the water, it helps in increasing the contact between the solid salt cube and the solvent (water). Stirring facilitates the movement of fresh water molecules towards the surface of the salt cube, resulting in faster dissolution.
Therefore, if Arjun stirs his cup of water, the rate at which the salt cube dissolves will speed up (Option A).