Question

“Water is a compound, not a mixture. “Explain this condition.

Answer 1

Hint: In compounds, two or more different elements are bonded to form compounds but in mixture there is no bonding of elements and they have variable composition. Now, answer the statement.
Complete answer:
A compound is a substance in which two or more different elements (An element is that which consists of only one type of particles. These particles may be either atoms or molecules. E.g. sodium, copper, silver etc. all these contain atoms of one type only. In case of molecules two atoms combine to give their respective molecules. E.g. hydrogen, nitrogen and oxygen gases) combine i.e. get bonded together to form the compounds. water, ammonia, carbon dioxide etc.
           Like:
                                                $2{{H}_ {2}} +{{O}_ {2}} \to 2{{H}_ {2}} O$

A compound is a pure substance which has its definite composition and fixed structure and is not easily separated by physical means i.e. filtration, distillation, evaporation etc. but rate separated by chemical means like fractional distillation etc.
On the other hand, mixtures are made up of two or more substances but in this the substances are not bonded together and each of them are having its own different properties and therefore, their ratio is not definite and thus, they have variable composition. They can be easily separated by physical methods like filtration, hand picking, distillation etc. E.g. sugar solution, dry air etc.
So, from the above discussed definitions, it is clear that the water is a compound and not a mixture because it is made up of only one kind of element i.e. oxygen and hydrogen atoms and hence, is a diatomic molecule.

Note: Don’t get confused in the molecules and compounds. The molecules are made up of two or more similar atoms of the same element while the compounds are made up of two or more atoms of different elements.