Why does alkali metals impart characteristic colour to the flame?

Give reasons for the following: a. Alkli metals do not occur free in nature. b. Alkali metal salts impart characteristic colour to the flame. c. Caesium is used in photoelectric cell. d. Alkali metals are good reducing agents in aqueous medium.

Assign reasons for the following (i) alkali metals impart characteristic colour to flame (ii) Alkali metals are strong reducing agents. (iii) An aqueous solution of Na_(2)CO_(3) is basic in nature.

Which alkali metal imparts pale violet colour to the flame?

Which of the following does/do not impart characteristic colour to the flame?

which of the following statement is not correct? (A) All alkali-metals salts impart a characteristic colour to the Bunsen flame. (B) The correct order of increasing thermal stability of the carbonates of alkali metals is Li_(2)CO_(3) (C) Among the alkali metal's cesium is the most reactive. (D) The reducing character of the alkali metal hydrides follow the order: "LiH>NaH>KH>RbH>CsH" ."]

The alkali metals & their salts impart characteristic colour to an:

Assertion (A): Magnesium does not impart any characteristic colour to the flame. Reason (R ): Due to small size and high effective nuclear charge, magnesium requires a large amount of energy for excitation of electrons.

Assertion : Berylium does not impart any characteristic colour to the Bunsen flame. Reason : Due to its very high ionization energy, beryllium requires a large amount of energy for excitation of the electrons.