Nigel Baldwin | Sodium metal reacting with water in a beaker 1 MVI 1322 @nigelbaldwin3184 | Uploaded March 2018 | Updated October 2024, 10 hours ago.
High School Chemistry

The reaction of sodium metal with water.

A small piece of sodium metal, approx. 0.5cm diameter, is dropped into a beaker of water.

The sodium did not ignite or catch fire on this occasion.

Observations:
1 The sodium floats, sodium is less dense than water
2 Sodium reacts very quickly; a hissing sound is heard due to gas being produced and the sodium moves rapidly across the surface of the water
3 The sodium melts into a ball because the reaction is exothermic and generates enough heat to melt the metal, melting point of sodium metal approx. 98 C

sodium + water = sodium hydroxide + hydrogen

In this case, Universal Indicator was not added to the water, which is usually done to show the production of the alkali sodium hydroxide.