11.20. What happens when
(a) Borax is heated strongly,
(b) Boric acid is added to water,
(c) Aluminium is treated with dilute NaOH,
(d) BF₃ is reacted with ammonia?

(a) When borax is heated strongly, it loses water and swells into the white mass, which on further heating melts to form a transparent glassy solid called borax glass and borax bead.
Na₂B₄O₇10H₂O→ Na₂B₄O₇+ 10H₂O

Na₂B₄O₇ → 2NaBO₂+ B₂O₃

(b) When boric acid is added to water, it accepts electrons from