When the solid A is added to water, it dissolves with the evolution of a lot of heat and making little explosions to form two products B and C. The properties of products B and C are entirely different from those of solid . A as well as water. Moreover, products B and C cannot be reconverted into solid A and water. When another solid D is added to water, it dissolves with the absorption of a little heat to form a product E which cools down. The product E shows the properties of both, solid D as well as water. Moreover, product E can be converted into solid D and water. (a) What type of change occurs when solid A is dissolved in water ? Why ? (b) What type of change occurs when solid D is dissolved in water ? Why ? (c) Name a metal which you think could behave like solid A . Also name the products B and C. (d) Name the solid D if it is the one which is used in making ordinary dry cells. (e) Name the process by which D can be recovered from E.