Question

Name a white crystalline solid salt used to make hard water soft and potable.

Answer 1

Hint: To solve this question one can think of any chemical compound that can be used to convert hard water into soft water or potable water. Hard water generally has so many salts present in it which give the water hard nature. So, one can think about any chemical which can minimize the salt concentration in hard water and elaborate the same in the answer.

Complete step by step answer:
-First of all we will learn about what is the meaning of hard water. The hard water can be explained as the water that contains the composition of high minerals in it. The formation of Hard water is due to water percolation through the deposits of limestone, gypsum, or chalk which are largely formed by the composition of magnesium and calcium carbonates and bicarbonates.
-Now let's learn about the meaning of soft water, where soft water can be explained as surface water which contains low concentrations of ions in it and more particularly the low concentrations in ions of magnesium and calcium. The soft water is present naturally at the places where the rainfall and the drainage basin of rivers are formed of calcium-poor rocks and hard rocks.
-The white crystalline solid salt used to make hard water soft and potable is sodium carbonate which is the inorganic compound that has the molecular formula as $N{a_2}C{O_3}$ and ${\text{Na}}$ acts as an inorganic element.
-The sodium carbonate is a crystalline solid where all the forms of it are present as white-colored and water-soluble salts that produce moderately alkaline solutions in water.

Note: The sodium carbonate is generally used for the softening of hard water by removing $M{g^{2 + }}$ and $C{a^{2 + }}$ ions. These ions when reacted with carbonate ions precipitate the insoluble solid. The sodium carbonate is also known as washing soda or soda ash and this method is used as an inexpensive method to convert hard water into soft water.