Question

Use the periodic table to answer the following questions.

(a)Identify an element with five electrons in the outer subshell. (b)Identify an element that would tend to lose two electrons.
(c) Identify an element that would tend to gain two electrons.
(d) Identify the group having metalloid, non-metal, liquid as well as gas at the room temperature.

Answer 1

(a) The electronic configuration of an element having 5 electrons in its outermost subshell should be $n{s}^{2}n{p}^5$. This is the electronic configuration of the halogen group. Thus, the element can be F, Cl, Br, I, or At.

(b) An element having two valence electrons will lose two electrons easily to attain the stable noble gas configuration. The general electronic configuration of such an element will be $n{s}^2$. This is the electronic configuration of group 2 elements. The elements present in group 2 are Be, Mg, Ca, Sr, Ba.

(c) An element is likely to gain two electrons if it needs only two electrons to attain the stable noble gas configuration. Thus, the general electronic configuration of such an element should be $n{s}^{2}n{p}^4$. This is the electronic configuration of the oxygen family.

(d) Group 17 has metalloid, non–metal, liquid as well as gas at room temperature. F and Cl are the gaseous states, Br is liquid state and I is solid state. Here, the F, Cl, Br and I are non-metals whereas, At is metalloid.