Question

Compounds called pure substances where as mixtures are not. Why?

Answer 1

Bcoz compounds are made up of elements in a fixed ratio I.e. water will always have 2hydrogen and 1oxygen anywhere on the planet whereas mixture of iron and sulphur(without heating) will not be in fixed ratio,iron can be more than sulphur at the same time more sulphur can be added to unbalance it

Answer 2

Pure elements are Substances which are made up of only one kind of atom. Air is a mixture of element and compound whereas alcohol in water is a mixture of compounds. CO2 is a pure compound and not an element.