Why do alkaline earth metals and their compounds impart characteristic colours to the flame?

Alkaline earth metals show:-

(a). Which alkaline earth metals do not give characteristic colour to the Bunsen flame? (b). Why alkaline earth metals do not form tripositive ions? (c ). Why alkaline earth metals are diamagnetic, but alkali metals are paramagnetic? (d). Why the first inonisation enthaply pf alkaline earth matals is higher than those of corresponding alkali metals? (e). Why alkaline earth metals are less electropositive than corresponding alkali metals?

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

Lithium compounds impart ........colour to the flame.

Which alkaline earth metal compound is volatile

How many alkaline earth metals are known?

How do alkaline earth metals occur in nature ?

What is flame test and why do alkali metals show characteristic colours in 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.

How many of the following metal chlorides impart characteristic colour to the lower oxidising flame? LiCl, NaCl, KCl, BeCl_(2), MgCl_(2), CaCl_(2), SrCl_(2), BaCl_(2)