A double replacement reaction can be best described as a reaction in which a substitution takes place.
two atoms of a compound are lost.
ions are exchanged between two compounds.
electrons are exchanged between two atoms.

each chemical family is represented as a group or column on the periodic table. based on chemical properties, there are 6 types of chemical families. group 1 represents alkali metals, group 2 represents alkaline earth metals, groups 3 to 12 represent transition metals, groups 13 to 16 represent non-metals and other metals, group 17 represents halogens and group 18 represents noble gases.

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