Hello!
The reaction that the graph represents is
A. Exothermic because Hrxn=-167 kJTo calculate Hrxn we apply the following equation:

Looking at the graph, and at the result of the calculations, we can see that the enthalpy of the products is
lower than the enthalpy of the reagents, because the sign is negative. That means that the reaction
releases energy in the form of heat and that the reaction is
exothermic.
Have a nice day!
The correct answer is option d, that is, the solubility of a solid is highly dependent on temperature.
Solubility refers to the maximum amount of a component, which will get dissolved in a given concentration of solvent at a particular temperature. The temperature influences the solubility of both gases and solids. The temperature has a direct influence on solubility.
For most of the ionic solids, enhancing the temperature elevates how briskly the solution can be formed. With the increase in temperature, the movement of the solid particles takes place briskly that enhances the chances that they will associate with the majority of the solvent particles. This leads to enhancing the rate at which the solution takes place.