Answer:
C. KBr is about twice as soluble as NaCl at 60°C
Explanation:
From the graph of solubility of various solutes with respect to temperature we can figure-out that on y-axis we have the increasing solubility of the solvents in gram per 100 gram of water as we move upwards and on x-axis we have increasing temperature of the solvent (water) moving rightwards.
As we move vertically up through 60°C line we notice that NaCl has solubility nearly 40 grams per 100 gram of water whereas on further moving up in the same line we find that KBr has nearly 80 gram per 100 gram of solubility.
The solubility of NaCl varies negligibly with change in the temperature of water whereas the solubility of KNO3 is greatly increased by the increasing temperature.
- Solid solutes have a tendency to dissolve highly in the water with increase in temperature because of increased inter molecular space of the solvent molecules on heating and loosening of the bonds of solid solute.
- But in case of a gaseous solute the tendency to dissolve into water decreases with increase in temperature because here if the kinetic energy of the molecules increases for the solute then its molecules will escape from the solvent.
