Select Page

Sodium reacts with water to produce sodium hydroxide and hydrogen gas


Remember: An ion is an atom or molecule that is positively or negatively charged due to loss or gain of electron(s).

Valence electrons are electrons in the outermost shell of an atom. The rule of octet says that atoms prefer to have 8 valence electrons to be stable or they'll become reactive.

sodium and water balanced equation
Sodium is a reactive metal of the alkali metal group. Its atomic number is 11, it has 11 protons,12 neutrons and 11 electrons.

  • Sodium is very unstable and highly reactive because it has only 1 valence electron in the outermost shell.
  • What happens if you add sodium, Na(+) to water?
  • Sodium explodes with water. The reaction is exothermic as it gives off a lot of heat.
  • Water, H2O, is made up of a hydroxide OH(-) ion and an H(+) ion.
  • When Sodium is placed in water, it displaces H in H2O.
  • Hydrogen quickly forms hydrogen gas (H2).
  • Hydrogen gas is flammable and catches fire easily.
  • Sodium has 1 valence electron which it easily gives up. Sodium becomes a positive ion (Na+).
  • Sodium and hydroxide will combine to become Sodium Hydroxide (Na+) + (OH-) --> NaOH
  • Meanwhile the valence electron is transferred from sodium to the hydrogen ion. It converts hydrogen ion back into a hydrogen atom again.
  • The hydrogen atom now becomes freely available to bond with another hydrogen atom to produce a gas.
Share