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?

In the periodic table,metallic character of the elements shows which one of the following trends?

The correct order of the non-metallic character among the elements $B, C, N, F$ and $Si$ is

In a periodic table, how does the basic character of oxides vary?

The electronic configurations of four elements are:
$I.$ $[Kr]\, 5s^1$
$II.$ $[Rn]\, 5f^{14}\, 6d^1\, 7s^2$
$III.$ $[Ar]\, 3d^{10}\, 4s^2\, 4p^5$
$IV.$ $[Ar]\, 3d^6\, 4s^2$
Consider the following statements:
$(i)$ $I$ shows variable oxidation state
$(ii)$ $II$ is a $d$-block element
$(iii)$ The compound formed between $I$ and $III$ is covalent
$(iv)$ $IV$ shows single oxidation state
Which statement is True $(T)$ or False $(F)$?

How many oxides among the following are basic in nature?
$As_2O_3, Na_2O, MgO, Mn_2O_3, CaO, ZnO, N_2O, N_2O_5$