Classification of elements and periodicity in properties practice · Medium

Which of the following properties is inversely related to electronegativity?

The set representing the correct order of first ionisation potential is:

Successive first five ionisation energies of a particular element is 7.1, 14.3, 34.5, 46.8, 162.2 (in eV) respectively. The element is likely to be

The five successive ionisation energies of the element are $800,2427,3658,25024$ and $32824 \mathrm{~kJ} \mathrm{~mol}^{-1}$ respectively. The number of valence electrons is :

Which of the following groups of elements have highly negative electron gain enthalpy?

The statement that is not correct for the periodic classification of elements is

The first ionisation enthalpy of $Na$ is 5.1 eV, the value of electron gain enthalpy of $N{a^ + }$ will be

The incorrect statement among the following is

The element with Z = 120 (not yet discovered) will be an/a

The tendency towards formation of coloured ions is the maximum in:

The factor not affecting the ionization enthalpy is

The first ionisation enthalpy values of third period element, $\mathrm{Na}, \mathrm{Mg}$ an $\mathrm{Si}$ are respectively $496,737$ and $786 \mathrm{~kJ} \mathrm{~mol}^{-1}$. The first $\Delta_\mathrm{i} \mathrm{H}$ value for $\mathrm{Al}$ will be close to

Which of the following statement is incorrect?

The molecular formula of chloride of Eka-Aluminium and Eka-Silicon respectively are

The magnitude of screening effect depends upon the number of

Assertion : Atomic size along a period decreases.

Reason : $Z_{\text {eff.}}$ in a period decreases.

Given below are two statements:
Statement I: The correct order of first ionization enthalpy values of $\mathrm{Li}, \mathrm{Na}, \mathrm{F}$ and $\mathrm{Cl}$ is $\mathrm{Na} < \mathrm{Li} < \mathrm{Cl} < \mathrm{F}$.
Statement II: The correct order of negative electron gain enthalpy values of $\mathrm{Li}, \mathrm{Na}, \mathrm{F}$ and $\mathrm{Cl}$ is $\mathrm{Na} < \mathrm{Li} < \mathrm{F} < \mathrm{Cl}$
In the light of the above statements, choose the correct answer from the options given below:

Which pair of ions are isoelectronic?

Which of the following obeys triad law :

Considering the elements $F,\,\,\,Cl,\,\,\,O$ and $N$ the correct order of their chemical reactivity in terms of oxidizing property is

Out of the four blocks in which periodic table is divided, helium belongs to which block?

The first ionization potentials $(\mathrm{eV})$ of ${N}$ and ${O}$ respectively are

Identify the correct order of the size of the following

The first second and third ionisation energies $\left( {{E_1},{E_2}\,\,and\,\,{E_3}} \right)$ for an element are $7\,\,eV,12.5\,\,eV$ and $42.5\,\,eV$ respectively. The most stable oxidation state of the element will be

In which of the following pairs the radii of second species is greater than that of first?

Which one pair of atoms or ions will have same configuration?

Which is not arranged in the correct sequence

Assertion (A): Electron gain enthalpy becomes less negative as we go down a group.
Reason (R): Size of the atom increases on going down the group and the added electron would be farther away from the nucleus.

Assertion : Atomic radius of inert gases are largest in the period

Reason : Effective nuclear charge of inert gases are minimum

The five successive ionisation enthalpies of an element are $\mathrm{800, 2427, 3658, 25024 \,\,and\,\, 32824\,\, kJ \,mo}{\mathrm{l}^{ - 1}}.$ The number of valence electrons in the element is