The periodic table: elements grouped by similar properties. Group: each column in the periodic table. Elements in the same group have similar chemical properties. Elements in the same row increase their numbers of electrons by one as you move from left to right. Group viiia are the inert gases: 8 ve"s. Group viia are the halogens: 7 ve"s. Group ia are the alkali metals: 1 ve. Group iia are the alkaline earths: 2 ve"s. All elements in the same group or column have the same number of valence electrons. The chemical proeprties of an atom are largely determined by its valence shell of electrons. Elements having the same numbers of valence electrons will behave in a similar chemical way. Strontium can replace calcium (both alkaline earth elements) in bones. In the event of a nuclear accident, radioactive strontium can be released into the atmosphere from which it settles out on the ground and enters the food change.
