Q10 of 58 Page 1

Four elements P, Q, Rand have atomic numbers 12, 13, 14 _and 15 respectively.

Answer the following questions giving reasons:


(i)What is the valency of Q?


(ii)Classify these elements as metals and non-metals.


(iii)Which of these elements will form the most basic oxide?

The electronic configuration of following elements are:



(i) The element Q has three valence electrons. So it loses 3 electrons to gain its stable gas configuration. So, the valency of Q is 3.


(ii) Since P and Q looses 2 and 3 electrons to obtain stable gas configuration, So P and Q are metals. Elements R and S either loses or gain electrons to gain its stable gas configuration. So R and S are Non-metals.


(iii) Since P is the most metallic element among P, Q, R and S. So element P will form the most basic oxide.


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