Use the periodic table to answer the following questions

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elementperoidicity

#1

Use the periodic table to answer the following questions.
(i) Identify an element with five electrons in the outer subshell.
(ii) Identify an element that would tend to lose two electrons.
(iii) Identify an element that would tend to gain two electrons.
(iv) Identify the group having metal, non-metal, liquid as well as gas at the room temperature.


#2

(i) General electronic configuration of elements having five electrons in the outer sub shell is${{ns}^{2}}$ ${{np}^{5}}$. This configuration belongs to halogen family, i.e., F, Cl, Br, I, At.
(ii) Elements of second group are known as alkaline earth metals [Mg, Cs, Sr, Ba, etc). Their general electronic configuration for valence shell is ${{ns}^{2}}$. These elements form dipositive cations by the lose of two electrons easily.
(iii) 16th group elements such as O, S, Se, etc., have a tendency to accept two electrons because by the gain of two electrons they attain noble gas configuration. Their general electronic configuration for valence shell is ${{ns}^{2}}$${{np}^{4}}$.
(iv) Group 1 or 17 of the periodic table contains metal, non-metal, liquid as well as gas at the room temperature, e.g., H 2 is a non-metal and in gaseous state at room temperature. All other elements of this group are metals. Cs is a liquid metal. Similarly, Br 2 is a liquid non-metal while other elements of this group are gaseous non-metals. Iodine can form ${{I}^{+}}$ so it has some what metallic properties.