(1) BeO(s) Amphoteric in nature
(2) NaHCO3 (crystalline) Amphoteric in nature, Imparts characteristic colour to Bunsen Flame,
Shows H-bonding and Have a chain structure
(3) BeCl2 Have a chain structure
(4) CsO2 Imparts characteristic colour to Bunsen Flame and Produces H2O2 and O2 on reaction with H2O