Question

residual solution remains colourless when sodium is added to cold water but turns turbid when calcium is added to the same

Answer 1

Sodium metal reacts rapidly with waterto form a colourless basic solution ofsodium hydroxide (NaOH) and hydrogen gas (H2). The reaction continues even when the solution becomes basic. The resulting solution is basic because of the dissolved hydroxide.

Answer 2

Answer:

sodium is highly soluble in water therefore when we add sodium in water a colourless solution is obtained whereas, calcium is moderately soluble in water hence, a turbid solution is obtained .