Consider the following elements:

Ca, Cl, Na, I, Li, Ba, Sr, K, Br


Separate these elements into three groups (families) of similar properties. State one property in each on the basis of which you have made your choice.

Li, Na and K, these elements from the above elements are the alkali metals and they have 1 electron in its valence shell.

Ca, Sr and Ba, these three elements from the above elements are the alkaline earth metals and having 2 electrons in its valence shell.


Cl, Br and I, these elements from the above elements are the non metals and also termed as Halogens.


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