predict what would occur if the following were placed in water?

- Beryllium
Beryllium does not react with water.

- Strontium
Strontium reacts steady with water to give strontium hydroxide and hydrogen gas. The reaction of strontium with water is faster than that of calcium.
Sr(s) + 2H₂O(l) → Sr(OH)₂(aq) + H₂(g)

- Chlorine
Chlorine dissolves in water to form chlorine solution. In chlorine solution, chlorine reacts reversibly with water to give hydrochloric acid and hypochlorous acid.
Cl₂(aq) + H₂O(l) ⇌ HCl(aq) + HOCl(aq)

- Rubidium
Rubidium reacts explosively with water to give rubidium hydroxide and hydrogen gas.
2Rb(s) + 2H₂O(l) → 2RbOH(aq) + H₂(g)