Three elements $X$,$Y$ and $Z$ are in the $3^{rd}$ period of the periodic table. The oxides of $X$,$Y$ and $Z$,respectively,are basic,amphoteric and acidic. The correct order of the atomic numbers of $X$,$Y$ and $Z$ is:

Which one of the following orders represents the correct sequence of increasing basic nature of the given oxides?

The electronic configuration of an atom $A$ is $1s^2, 2s^2 2p^6, 3s^2 3p^6 3d^{10}, 4s^2 4p^3$. The chemistry of $A$ is therefore likely to be similar to that of:

In $s-$block,on moving down the group,the reactivity of metals with water and air increases. Which of the following factors has no significance for this trend of reactivity?

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:

Which elements are classified as metalloids? Name them.