Alkali metals, though white, impart characteristic color to the flame because of
1. | excitation and coming back of valence electrons to the original level. |
2. | oxidation of metal in the presence of flame. |
3. | excitation of valence electrons. |
4. | gain of electrons. |
Ionic mobility of which of the following alkali metal ions is lowest when aqueous solution of their salts are put under an electric field?
1. K
2. Rb
3. Li
4. Na
Among the following which one has the highest cation to anion size ratio?
1. CsF
2. LiF
3. NaF
4. CsI