Tow elements with symbol x atomic no 11 and Y atomic no 13 period 3 of periodic table
Answers
Two elements with symbol X (atomic no. 11) and Y (atomic no. 13) are
placed in the III period of the modern periodic table -
(i) Which amongst the two has more metallic character?
(ii) Calculate the valency of each element.
(iii) Element ‘Y’ is smaller than ‘X’ in terms of atomic size. Is the
statement true, justify?
hey mate!
The atomic number of element X is 11, so its electronic configuration is 2, 8, 1. This element belongs to the first group of the periodic table. The atomic number of element Y is 13. Its electronic configuration is 2, 8, 3 and it belongs to the 13th group of the periodic table. So
(1) Element X has more metallic character. This is because element Y occurs in the same period as element X and as we move from left to right in a period, the metallic character decreases.
(2) The valency of element X is 1, while that of Y is 3.
(3) Across a period the atomic size decreases because as we move from left to right, both nuclear charge and number of electrons increase by a factor of one, but the electrons are added to the same shell. As a result of this increased nuclear charge, the attraction between the nucleus and the valence electrons increases because of which they are pulled closer to the nucleus. Thus the size of atoms decreases as we move from left to right in a period.
So, the statement that element Y is smaller than element X in terms of atomic size is correct.