Which of the following is most acidic?

Which of the following ions has a pseudo-noble gas electronic configuration?

Which of the following is/are amphoteric oxide$(s)$?

On moving down the group,which of the following properties gradually increases?

Considering the atomic number and position in the periodic table,arrange the following elements in the increasing order of metallic character: $Si$,$Be$,$Mg$,$Na$,$P$.

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: