Which one of the following is an incorrect statement?

The ground state electronic configurations of the elements,$U, V, W, X,$ and $Y$ (these symbols do not have any chemical significance) are as follows:
$U: 1s^2 2s^2 2p^3$
$V: 1s^2 2s^2 2p^6 3s^1$
$W: 1s^2 2s^2 2p^6 3s^2 3p^2$
$X: 1s^2 2s^2 2p^6 3s^2 3p^6 3d^5 4s^2$
$Y: 1s^2 2s^2 2p^6 3s^2 3p^6 3d^{10} 4s^2 4p^6$
Determine which sequence of elements satisfies the following statements:
$(i)$ Element forms a carbonate which is not decomposed by heating
$(ii)$ Element is most likely to form coloured ionic compounds
$(iii)$ Element has the largest atomic radius
$(iv)$ Element forms only acidic oxide

Identify the incorrect order.

Which of the following statements are true?
$A.$ Unlike $Ga$ that has a very high melting point,$Cs$ has a very low melting point.
$B.$ On Pauling scale,the electronegativity values of $N$ and $Cl$ are not the same.
$C.$ $Ar$,$K^{+}$,$Cl^{-}$,$Ca^{2+}$,and $S^{2-}$ are all isoelectronic species.
$D.$ The correct order of the first ionization enthalpies of $Na$,$Mg$,$Al$,and $Si$ is $Si > Al > Mg > Na$.
$E.$ The atomic radius of $Cs$ is greater than that of $Li$ and $Rb$.
Choose the correct answer from the options given below

Which of the following properties does not depend on periodicity?

Among the elements $B$,$Al$,$C$,and $Si$,
$(a)$ which element has the highest first ionisation enthalpy?
$(b)$ which element has the most metallic character? Justify your answer in each case.