Why is distilled water preferred over tap water in practical chemistry?

Distilled water is preferred in practical chemistry primarily because it contains fewer chemical impurities. Distillation is a process that involves boiling water and then condensing the steam back into a liquid, which effectively removes many dissolved solids, minerals, and organic compounds that may be present in tap water. These impurities can interfere with chemical reactions, alter the results of experiments, and compromise the accuracy of analytical measurements.

Using distilled water helps to ensure that the experimental conditions remain consistent and that any reactions or measurements are not affected by unwanted contaminants. This is particularly important in sensitive analyses and high-precision techniques, where even small amounts of impurities could lead to significant errors or misleading results.

In contrast, tap water may contain various minerals, chlorine, and other chemicals added for treatment purposes, which can contribute to inconsistencies in experimental outcomes. Therefore, the purity of distilled water makes it the ideal choice for laboratory work.