Arrange the following acids in the decreasing order of their acidic strength: $Cl(OH) \ (I)$,$Br(OH) \ (II)$,$I(OH) \ (III)$.

Which of the following electronic configurations represents a coinage metal?

The correct order of acid strength is

Arrange the following oxides in the increasing order of their basic nature: $(a) Al_2O_3, (b) K_2O, (c) P_2O_5, (d) MgO$.

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 of the following elements with the given electronic configurations belong to the same group?
$(i)$ $1s^2 2s^2$
$(ii)$ $1s^2 2s^2 2p^5$
$(iii)$ $1s^2 2s^2 2p^6 3s^2 3p^5$
$(iv)$ $1s^2 2s^2 2p^6 3d^{10} 4s^1$