Question

how will you justify that ice ,water and water vapours are the three states of a substance not a substance

Answer 1

Ice ,water and water vapour are the three states of matter because they are having features of solid ,liquid and gas respectively.
These are only physical features.we can justify that they are not different substantances by stating and proving that they are not chemically different.Chemically ,it is H2O and the components in it are hydrogen and oxygen of same proportion.(lt is chemical constituents of substances that distinguish from one another).Not only ,lce can b convertd into water and watr into vaper and vise versa.That is ,they r reversible hence they r physical changes not chemical changes.
Thus v can state that ice ,water and vapour are jst states of substance but r not different substances

Answer 2

Ice ,water and water vapour are the three states of matter because they are having features of solid ,liquid and gas respectively.
These are only physical features.we can justify that they are not different substantances by stating and proving that they are not chemically different.Chemically ,it is H2O and the components in it are hydrogen and oxygen of same proportion.(lt is chemical constituents of substances that distinguish from one another).Not only ,lce can b convertd into water and watr into vaper and vise versa.That is ,they r reversible hence they r physical changes not chemical changes.
Thus v can state that ice ,water and vapour are jst states of substance but r not different substances