Periodic Table and Periodicity · Chemistry · TS EAMCET

If first ionisation enthalpy $\left(\Delta_{i} H\right)$ values of $\mathrm{Na}, \mathrm{Mg}$ and Si are respectively 496,737 and $786 \mathrm{~kJ} \mathrm{~mol}^{-1}$, the first ionisation enthalpy value of $\mathrm{Al}\left(\mathrm{in} \mathrm{kJ} \mathrm{mol}^{-1}\right.$ ) will be

The set containing the elements with positive electron gain enthalpies is

Assertion (A) : The ionic radii of $\mathrm{Na}^{+}$and $\mathrm{F}^{-}$are same.

Reason (R) : Both $\mathrm{Na}^{+}$and $\mathrm{F}^{-}$are isoelectronic species.

The correct answer is

In which of the following ionic pairs, second ion is smaller in size than the first ion?

In which of the following species, the ratio of $s$-electrons to $p$-electrons is same?

Identify the pair of elements in which the difference in atomic radii is maximum

Match the following.

List I (Element)	List II (Block)
A Ra	I p - block
B Uuq	II s- block
C Ds	III f - block
D Fm	IV d - block

The correct answer is

Identify the pair of element in which the number of $s$-electrons to $p$-electrons ratio is $2: 3$

Which of the following has the least electron gain enthalpy?