Question

Element E and F have atomic number 14 and 17 respectively. Find their position in the periodic table.
(A) E🡪3rd period; 14th group, F🡪3rd period; 17th group
(B) E🡪4rd period; 14th group, F🡪4rd period; 17th group
(C) E🡪4rd period; 17th group, F🡪4rd period; 14th group
(D) E🡪3rd period; 17th group, F🡪3rd period; 14th group

Answer 1

Hint: The periodic table with more changes in the time was originally developed by Mendeleev and Moseley. This periodic table is an arrangement of the elements in order of their atomic numbers appearing as a vertical column is a group and a period is a horizontal row in the periodic table.

Complete step by step solution:
A periodic table is arranged in order of atomic number. A group and a period are vertical rows, a horizontal row of the periodic table.
There are seven periods and 18 groups in the periodic table. Both in periods and groups, elements are arranged based on their atomic number. In groups, the atomic number of the element increases from down to the group. In periods, the atomic number of the element increases from left to right.
Out of seven periods in the periodic table, period 1 has only two elements, period 2 and 3 have only 8 elements, periods 4 and 5 have 18 elements. Period 6 and 7 have 32 elements due to these periods being separated as two bottom rows from the periodic table.
Total 18 groups, the first two groups are 1A, 2A, remaining groups are from 3A to 8A and the remaining groups are represented with B in their titles.
Given element E atomic number 14 is silicon and F atomic number 14 is Cl.
Si electronic configuration = $[Ne]3{{s}^{2}}3{{p}^{2}}$
Cl electronic configuration = $[Ne]3{{s}^{2}}3{{p}^{5}}$
From the above configuration indicates that both Si and Cl from the 3rd period and based on the general configuration of groups Si belongs to the carbon family which is represented as the 14th group, Cl belongs to halogens which are from the 17th group.
Hence, element E belongs to the 3rd period and 14th group, element F belongs to the 3rd period and 17th group

The correct answer is option A.

Note: The general configuration of the 14th group is \[n{{s}^{2}}n{{p}^{2}}\] which is named as the carbon family. The general configuration of the 17th group is \[n{{s}^{2}}n{{p}^{5}}\] which is known as halogens. In this configuration, n represents the number of periods of the element in that group.