It is the second book in the series of basic chemistry. First book deals with some elementary concepts like from what the matter around us made up of? Why some substances react and some not? In this book we will try to explore, actually what happens when these substances react? What are the factors which govern these reactions? We shall also perceive the properties of these substances. For our convenience we will categories the substances as acid, base, salt, metal, non-metal and carbon compounds. In the last chapter our emphasis will be at the classification of elements.