Classification of Elements and Periodicity — JEE Main PYQs

Given below are two statements : one is labelled as Assertion A and the other is labelled as Reason R:

Assertion A: The first ionisation enthalpy decreases across a period.
Reason R: The increasing nuclear charge outweighs the shielding across the period.
In the light of the abo …

The element having the highest first ionization enthalpy is

Given below are two statements:

Statement I: Fluorine has most negative electron gain enthalpy in its group.
Statement II: Oxygen has least negative electron gain enthalpy in its group.
In the light of the above statements, choose the most appropriate from the options given belo …

The correct sequence of electron gain enthalpy of the elements listed below is
A. Ar
B. Br
C. F
D. S

Choose the most appropriate from the options given below:

Given below are the two statements: one is labeled as Assertion (A) and the other is labeled as Reason (R).

Assertion (A): There is a considerable increase in covalent radius from N to P. However from As to Bi only a small increase in covalent radius is observed.

Reason (R): co …

If IUPAC name of an element is "Unununnium" then the element belongs to nth group of periodic table. The value of $n$ is ____

Consider the following elements.

Which of the following is/are true about A', B', C' and D'?
A. Order of atomic radii: B'<A'<D'<C'
B. Order of metallic character : B'<A'<D'<C'
C. Size of the element: D'<C'<B'<A'
D. Order of ionic radii : B'⁺<A'⁺<D'⁺<C'⁺

Choose the correct answe …

Given below are two statements:

Statement - I: Along the period, the chemical reactivity of the element gradually increases from group 1 to group 18.
Statement - II: The nature of oxides formed by group 1 element is basic while that of group 17 elements is acidic.
In the the lig …

The difference between electron gain enthalpies will be maximum between:

Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R.
Assertion A: The energy required to form ${\mathrm{Mg}}^{2+}$ from Mg is much higher than that required to produce ${\mathrm{Mg}}^{+}$.
Reason R: ${\mathrm{Mg}}^{2+}$ is small ion and …

The correct order of metallic character is:

The correct order of electronegativity for given elements is:

For elements $\mathrm{B},\mathrm{C},\mathrm{N},\mathrm{Li},\mathrm{Be},\mathrm{O}$ and F the correct order of first ionization enthalpy is

Inert gases have positive electron gain enthalpy. Its correct order is

Which of the following represents the correct order of metallic character of the given elements?

Which one among the following metals is the weakest reducing agent ?

The correct order of hydration enthalpies is
(A) ${\mathrm{K}}^{+}$
(B) ${\mathrm{Rb}}^{+}$
(C) ${\mathrm{Mg}}^{2+}$
(D) ${\mathrm{Cs}}^{+}$
(E) ${\mathrm{Ca}}^{2+}$

Choose the correct answer from the options given below:

Given below are two statements:

Statement I: The decrease in first ionization enthalpy from B to Al is much larger than that from Al to Ga.
Statement II: The d orbitals in Ga are completely filled.
In the light of the above statements, choose the most appropriate answer from the …

For electron gain enthalpies of the elements denoted as ${\Delta }_{\mathrm{eg}}\mathrm{H}$, the incorrect option is :

Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason (R)
Assertion (A) : The first ionization enthalpy of 3d series elements is more than that of group 2 metals

Reason (R) : In 3d series of elements successive filling of d-orbital …

The correct increasing order of the ionic radii is

In which of the following pairs, electron gain enthalpies of constituent elements are nearly the same or identical?
(A) Rb and Cs
(B) Na and K
(C) Ar and Kr
(D) I and At

Choose the correct answer from the options given below:

The correct decreasing order for metallic character is

The incorrect statement is

The IUPAC nomenclature of an element with electronic configuration $[\mathrm{Rn}]5{\mathrm{f}}^{14}6{\mathrm{d}}^{1}7{\mathrm{s}}^2$ is :

Outermost electronic configurations of four elements $\mathrm{A},\mathrm{B},\mathrm{C},\mathrm{D}$ are given below:
(A) $3{\mathrm{s}}^2$
(B) $3s^{2}3p^1$
(C) $3s^{2}3p^3$
(D) $3s^{2}3p^4$

The correct order of first ionization enthalpy for them is:

An element A of group 1 shows similarity to an element B belonging to group 2. If A has maximum hydration enthalpy in group 1 then B is:

The first ionization enthalpies of $\mathrm{Be},\mathrm{B},\mathrm{N}$ and O follow the order

Given two statements below:

Statement I: In Cl₂ molecule the covalent radius is double of the atomic radius of chlorine.

Statement II: Radius of anionic species is always greater than their parent atomic radius.

Choose the most appropriate answer from options given below:

The correct order of increasing ionic radii is

Element "E" belongs to the period 4 and group 16 of the periodic table. The valence shell electron configuration of the element, which is just above 'E' in the group is

Given below are two statements. One is labelled as Assertion A and the other is labelled as Reason R.

Assertion A: The first ionization enthalpy for oxygen is lower than that of nitrogen.

Reason R: The four electrons in 2p orbitals of oxygen experience more electron-electron re …

Which of the following elements is considered as a metalloid?

Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason(R)

Assertion (A): The ionic radii of ${\mathrm{O}}^{2-}$ and ${\mathrm{Mg}}^{2+}$ are same.

Reason (R) : Both ${\mathrm{O}}^{2-}$ and ${\mathrm{Mg}}^{2+}$ are isoelectronic species

In …

The first ionization enthalpy of $\mathrm{Na},\mathrm{Mg}$ and Si , respectively, are: 496,737 and $786\mathrm{kJ}{\mathrm{mol}}^{-1}$. The first ionization enthalpy $\left(\mathrm{kJ}{\mathrm{mol}}^{-1}\right)$ of Al is:

Given below are the oxides:
${\mathrm{Na}}_2\mathrm{O},{\mathrm{As}}_2{\mathrm{O}}_3,{\mathrm{N}}_2\mathrm{O},\mathrm{NO}$ and ${\mathrm{Cl}}_2{\mathrm{O}}_7$
Number of amphoteric oxides is:

The correct order of electron gain enthalpies of Cl, $\mathrm{F}$, $\mathrm{Te}$ and Po is

Consider the elements Mg, Al, S, P and Si, the correct increasing order of their first ionization enthalpy is:

The correct order of ionic radii for the ions, ${\mathrm{P}}^{3-},{\mathrm{S}}^{2-},{\mathrm{Ca}}^{2+},{\mathrm{K}}^{+},{\mathrm{Cl}}^{-}$ is:

Which one of the following statements for D.I. Mendeleeff, is incorrect?

Match List - I with List - II.

List - I
Electronic configuration of elements
(a) $1{\mathrm{s}}^{2}2{\mathrm{s}}^2$
(b) $1s^{2}2s^{2}2p^4$
(c) $1s^{2}2s^{2}2p^3$
(d) $1s^{2}2s^{2}2p^1$

List - II
${\Delta }_i\mathrm{H}$ in $\mathrm{kJ}{\mathrm{mol}}^{-1}$ …

The correct order of electron gain enthalpy is :

Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason (R).
Assertion (A) : Metallic character decreases and non-metallic character increases on moving from left to right in a period.
Reason (R) : It is due to increase in ionisation …

The absolute value of the electron gain enthalpy of halogens satisfies :

The ionic radii of ${\mathrm{K}}^{+},{\mathrm{Na}}^{+},{\mathrm{Al}}^{3+}$ and ${\mathrm{Mg}}^{2+}$ are in the order:

The CORRECT order of first ionisation enthalpy is:

The characteristics of elements $\mathrm{X}$, $\mathrm{Y}$ and Z with atomic numbers, respectively, 33, 53, and 83 are:

Identify the elements X and Y using the ionization energy values given below:
Ionization energy ( $\mathrm{kJ}/\mathrm{mol}$ )

The first ionization energy of magnesium is smaller as compared to that of elements $X$ and $Y$, but higher than that of $Z$. The elements $X,Y$ and $Z$, respectively are:

The set of elements that differ in mutual relationship from those of the other sets is: