If an element $X$ is placed in group $14$,what will be the formula and the nature of bonding of its chloride?

An element $X$,which is a yellow solid at room temperature,shows catenation and allotropy. $X$ forms two oxides which are also formed during the thermal decomposition of ferrous sulphate crystals and are major air pollutants.
$(a)$ What would be the nature (acidic/basic) of the oxides formed?
$(b)$ Locate the position of the element in the Modern Periodic Table.

An element $A$ has an atomic number $16$. To which group and period does it belong?

"Hydrogen occupies a unique position in the Modern Periodic Table". Justify the statement.

The element with atomic number $18$ belongs to which group?

An element which is an essential constituent of all organic compounds belongs to :