The electronic configuration of an element is $1s^2 2s^2 2p^6 3s^2 3p^3$. What is the atomic number of the element that lies immediately below this element in the periodic table?

Which of the following oxides is different from the other three oxides?

Which of the following represents the correct order of acidic strength?

Given below are two statements:
Statement-$I$: Along the period,the chemical reactivity of the elements gradually increases from group $1$ to group $18$.
Statement-$II$: The nature of oxides formed by group $1$ elements is basic,while that of group $17$ elements is acidic.
In the light of the above statements,choose the most appropriate answer from the options given below:

What is the correct order with respect to metallic property of $Zr, Cd, Sn, Sr$?

Consider the following four elements,which are represented according to the long form of the periodic table. Here $W$,$Y$,and $Z$ are left,up,and right elements with respect to the element $X$,and $X$ belongs to the $16^{th}$ group and $3^{rd}$ period. Then,according to the given information,the incorrect statement regarding the given elements is: