Question

Arrange the following elements in the order of their increasing non-metallic character.
Li, O, C, Be, F
A.$O < F < C < Be < Li$
B.$Li < Be < C < O < F$
C.$F < O < C < Be < Li$
D.$F < O < Be < C < Li$

Answer 1

Hint: Before answering this question, we should know that Non-metals have the ability to gain electrons in a chemical reaction but have a high attraction for electrons within a compound. The upper portion of the periodic table is occupied by most reactive nonmetals. As the noble gases are not reactive, they are considered a special group.

Complete answer:
To eliminate an electron from an atom needs energy in huge amounts to conquer the magnetic pull created by the positive charge of the nucleus. The I.E is always positive, As we move from left to right across a period, the ionization energy will always increase and as we move from top to the bottom, the ionization energy will decrease because the atomic number down the group increases results in the increase in the number of shells as well. The distance between the outermost electron and nucleus is so much that it can be easily removed. And as shells are increasing, the shielding effect will be more as well.
The outermost electrons will face a less effective nuclear charge compared to the actual nuclear charge. It happens because the electrons that are innermost shield the electrons which are outermost by causing hindrance in the path of nuclear charge.
When we move from right to left in a period, the metallic character increases resulting in a decrease in the non-metallic character due to the increase in the atomic size and the force of attraction between the nucleus and outermost electron decreases.
Therefore, the order will be

Option B :$Li < Be < C < O < F.$

Note:
There is not a clear distinction between metallic and non-metallic characters. There is an increase in the ability to accept electrons when we move across the periodic table, i.e Non-metallic. When the ability of an atom to donate electrons decreases, i.e Metallic.