The properties of a few elements are given below:
Element | A | B | C |
Melting point | |||
Atomic size | 120 pm | 131 pm | 136 pm |
Answer the following giving reasons:
Should the metallic character decrease or increase from A to C?
Step-1: Introduction
The elements in periodic table are placed in periods and groups. Periods are horizontal rows that has increasing atomic numbers. Groups are vertical columns. The groups have similar chemical properties. There are 7 periods and 18 groups in periodic table.
The elemental classification in the periodic table long form is electronic configuration.
Step-2: Atomic size
The electrons distance in the outermost shell from the atomic nucleus is atomic size. Atomic size downs on moving the period from left to right. But along the group, it increases.
From the given element C to A, atomic size decreases. So, it belongs to same period.
The solid starts to melt at a particular temperature and that point is melting point. Melting point rises from left to right reaches maximum at group 14 and then decreases in a period and it also decreases along the group.
From the given element C to A, the melting point decreases and belongs to same period.
Step-3: Metallic character
In periodic table, group 1, 2 are metals, group 17, 18 are non-metals, middle groups are transition metals and zig-zag line along the group 13 to 16 are metalloids.
So, the metallic character is higher on extreme right while the non-metallic character is higher towards the right of the periodic table.
Since the elements belong to same period, the metallic character from A to C increases.
Final answer:
Therefore, the metallic character increases from A to C.