Question

The element with atomic number 36 belongs to which block in the periodic table?
A.p
B.s
C.f
D.d

Answer 1

Hint: In chemistry, a symbol is used as an abbreviation to describe an element.
The atomic number or the proton number is displayed in the left subscript position of the element symbol to specify the element. This number defines the number of protons in the element.

Complete step by step answer:
The periodic table is divided into 4 blocks: s, p, d and f blocks.
The elements of group 13 to group 17 and also group 18 have one, two, three, four, five and six electrons respectively in the outermost p orbitals. The last electron in these elements enters the p orbital of the valence shell and hence they constitute the p-block elements. The general configuration of p-block elements is \[{\text{n}}{{\text{s}}^{\text{2}}}{\text{n}}{{\text{p}}^{{\text{1 - 6}}}}\] where n represents the outermost shell.
The element with atomic number 36 is the element krypton. It is a group 18 element and its electronic configuration is ${\text{1}}{{\text{s}}^{\text{2}}}{\text{2}}{{\text{s}}^{\text{2}}}{\text{2}}{{\text{p}}^{\text{6}}}{\text{3}}{{\text{s}}^{\text{2}}}{\text{3}}{{\text{p}}^{\text{6}}}{\text{3}}{{\text{d}}^{{\text{10}}}}{\text{4}}{{\text{s}}^{\text{2}}}{\text{4}}{{\text{p}}^{\text{6}}}$ . Thus, the outermost shell configuration is ${\text{4}}{{\text{s}}^{\text{2}}}{\text{4}}{{\text{p}}^{\text{6}}}$ . In other words, there are six electrons in the outermost p orbital of krypton and so it is a p block element. So, A is the correct option.
The s block elements are constituted by group 1 and group 2 elements as their last electrons enter the s orbital of the valence shell and so option B is wrong.
The elements of group 3 to group 12 constitute the d-block elements since in them, the 3d, 4d, 5d and 6d subshells are incomplete and the last electron enters the $\left( {{\text{n}} - 1} \right){\text{d}}$ orbital. So, option D is also wrong.
The elements in which the last electron enters the \[\left( {{\text{n}} - 2} \right){\text{f}}\] orbitals constitute the f block elements and so option C is also wrong.

So, A is the correct option.

Note:
The first member of each of the groups of p-block elements differ in many respects from the other heavier members of the same group.
This different behavior is due to the following reasons:
(i)The small size of the first element.
(ii) The high electronegativity of the first element and
(iii) The non-availability of d orbitals for bonding among the first row elements.