Think About This!
The alkali metals consist of the first column in the periodic table. These metals are grouped together because they have similar properties. For example, water reacts vigorously with each of the alkali metals. The video below shows this reaction for the metal potassium (K).
All of the alkali metal atoms have one electron in their outermost shell. Having only one electron in the outermost shell makes the electron very susceptible to being stolen by another atom or molecule. When two potassium atoms (K) each lose an electron to a water molecule (H2O), a hydrogen molecule (H2) and two hydroxide ions (-OH) are formed as well as two potassium ions (K+).