Elements M forms an ion, `M^(2+)` and element X forms an ion, `X^(2-)`. The electronic arrangements of these ions are shown as

Which of the following statements about the elements M and X is/are incorrect?
I. M is in group 2 and period 4 of the periodic table.
II. M is a non-metal and X is a metal.
III. X is in group 15 and period 2 of the periodic table.
IV. M and X form MX type compound.
V. On moving from M towards X in the periodic table, electronegativity decreases.

Options

A. Only II, III and V
B. Only I and IV
C. Only II
D. Only II and III

Answer

A

Explanation

From the given electronic arrangements of ions,
`M^(2+)` ion : 2, 8, 8 `X^(2-)` ion : 2, 8
Thus M: 2, 8,8,2 and X: 2,6
So, M is Ca and X is O
I. Ca is in group 2 and period 4 of the periodic table.
II. Ca is a metal and O is non-metal.
`therefore` Statement II is incorrect.
III. O is in group 16 and period 2 of the periodic table.
`therefore` Statement III is incorrect
IV Ca and O form CaO compound.
V. On moving from Ca towards O in the periodic table, electronegativity increases.
`therefore` Statement V is incorrect.