Question

Is distilled water a mixture?

Answer 1

Hint:We classify all the substances as pure or mixture. If the distilled water only contains one element or one compound then it will be considered as a pure substance and if it contains more than one element or compound then it will be considered as a mixture.

Complete step-by-step answer:All the substances surrounding us are either in the pure state or in the mixture form. A pure substance means it contains only one element or only one compound. For example, oxygen gas (${{O}_{2}}$), pure salt (NaCl), etc. Whereas the mixture means when the substance has more than one element or more than one compound. For example, salt dissolved in water, an alloy of copper and zinc, etc.
We know that tap water contains more components than hydrogen and water, i.e., salts of some metals like calcium, magnesium, etc. therefore, tap water is considered as a mixture.
When the tap water or normal water is heated and boiled in a flask connected with a condenser which is connected with another flask where the vapor of the water is recollected, we get the distilled water. This water doesn't contain any salts or ions because these impurities have a higher melting point and will remain back in the first flask.
So, the distilled water only contains water molecules, therefore, it is considered a pure substance and not a mixture. We can also call it deionized water.

Note:The mixtures are again divided into two parts: homogenous in which the two or more substances combine to form only one phase and heterogeneous in which there is more than one phase and can be distinguished.