Basic objective of this lecture is to discuss on Elements, Compounds and Mixtures. Here major focus on Matter, it is is a substance that occupy space and has mass. Matter can be classified into – Pure Matter and Impure Matter. If homogeneous matter cannot be separated by physical means, then the matter is a pure substance. If a pure substance can be decomposed into something else, then the substance is a compound. And if a pure substance cannot be decomposed into something else, then the substance is an element.