What property do all elements in the same column of the Periodic Table as boron have in common?

List any two properties of the elements belonging to the first group of the modern periodic table.

Three elements $X$,$Y$,and $Z$ having atomic numbers $11$,$7$,and $6$ respectively react with oxygen to form their oxides.
$(a)$ Arrange these oxides in increasing order of their basic nature.
$(b)$ Give reason for your answer.

Which of the following gives the correct increasing order of the atomic radii of $O$,$F$ and $N$?

The order of increasing atomic size is:

Taking the example of an element of atomic number $16$, explain how the electronic configuration of the atom of an element relates to its position in the modern periodic table and how valency of an element is calculated on the basis of its atomic number.