A metal (M) burns with dazzling brilliance in air to give a white powder. The white powder reacts with water to form a white precipitate and a colourless gas with a characteristic smell. The metal (M) decomposes hot water but not cold water, liberating the inflammable hydrogen gas. The metal (M) is:

Options

A. (a) K
B. (b) Ca
C. (c) Mg
D. (d) Rb

Answer

A