Question -
Answer -
(a) When sodiumcarbonate is added to water, it hydrolyses to give sodium bicarbonate andsodium hydroxide (a strong base). As a result, the solution becomes alkaline.
(b) It is not possible toprepare alkali metals by the chemical reduction of their oxides as theythemselves are very strong reducing agents. They cannot be prepared bydisplacement reactions either (wherein one element is displaced by another).This is because these elements are highly electropositive. Neither canelectrolysis of aqueous solutions be used to extract these elements. This isbecause the liberated metals react with water.
Hence,to overcome these difficulties, alkali metals are usually prepared by theelectrolysis of their fused chlorides.
(c) Blood plasma and the interstitial fluidssurrounding the cells are the regions where sodium ions are primarily found.Potassium ions are located within the cell fluids. Sodium ions are involved inthe transmission of nerve signals, in regulating the flow of water across thecell membranes, and in transporting sugars and amino acids into the cells.Hence, sodium is found to be more useful than potassium.