Question

tap water is mixture whereas pure water is a compound how

Answer 1

Tap water is somehow impure and we know that a mixture is chemically impure whereas pure water does not contains impurities so it is a compound

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.