Chemical substances how to make?

A chemical substance may well be defined as “any material with a definite chemical composition” which is unique to itself in terms of atomic structure and reactivity. It can either be a pure chemical element or a pure chemical compound. A chemical compound is a chemical substance that is composed of a particular set of atoms or ions. Two or more elements ( pure) combined into one substance through a chemical reaction form a chemical compound (often called as substance). All compounds are substances, but not all substances are compounds.

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How to make a chocolate CADBURY DAIRY MILK?

IF YOU EAT this chocolate a small piece or a very big piece in any where either in delhi or kolkata there will be no difference in taste.that means the ratio of milk, water,sugar and other things is remain same in its small piece or a very big piece.

In such a way if we analyse the substance WATER where ever you take it from either ganga river or yamuna river or any other river in any thing either in glass or a big jar it's taste do not vary because of same ratio of hydrogen and oxygen.

So In such a way chemical substances is made so that there properties do not vary with place and amount.