s-block element which cannot be qualitatively confirmed by the flame test is
- (A)Li
- (B)Na
- (C)Rb
- (D)Be✓ Correct
Answer: (D)
Solution
Most s-block elements give characteristic flame colors:
Beryllium (Be) does not impart any color to the flame due to its small size and high ionization energy. The energy from the flame is insufficient to excite the electrons to higher energy levels, so no characteristic emission occurs.
Therefore, Be cannot be qualitatively confirmed by the flame test.
- Li: Crimson Red
- Na: Yellow
- Rb: Red violet
- Be: No color
Beryllium (Be) does not impart any color to the flame due to its small size and high ionization energy. The energy from the flame is insufficient to excite the electrons to higher energy levels, so no characteristic emission occurs.
Therefore, Be cannot be qualitatively confirmed by the flame test.
JEE Main · 2022 · 26 Jun 2022 · Shift 2 · Single correct option