Of the following pairs,the one containing an example of metalloid elements in the periodic table is:

Explain the trends in chemical reactivity and properties across the periodic table.

The elements in which $s$ and $p$-orbitals are present are known as:

Why do elements in the same group have similar physical and chemical properties?

The oxide of a metal $(R)$ can be reduced by the metal $(P)$,and metal $(R)$ can reduce the oxide of metal $(Q)$. Then the decreasing order of the reactivity of metals $(P)$,$(Q)$,and $(R)$ with oxygen is:

What is the correct order of basicity of halides?