Question

name two metals which react violently with cold water. write any observation you would make when such a metal is dropped into water. how would you identify the gas involved, if any, during the reaction ? write the equations involved.

Answer 1

Sodium

When sodium is added to water, it melts to form a ball that moves around on the surface. It fizzes rapidly, and the hydrogen produced may burn with an orange flame before the sodium disappears.

Sodium + water → sodium hydroxide + hydrogen

2Na(s) + 2H2O(l) → 2NaOH(aq) + H2(g)

Potassium

When potassium is added to water, it melts and floats. It moves around very quickly on the surface of the water. The hydrogen ignites instantly. The metal is also set on fire, with sparks and a lilac flame. There is sometimes a small explosion at the end of the reaction.

Answer 2

Answer:

Sodium and potassium are two metals that react violently with cold water. Three observations when such a metal is dropped in water are: Reaction is highly exothermic i.e. a huge amount of heat is produced. Hydrogen gas is evolved in the reaction.

Explanation: