Classification of Elements and Periodicity in Properties

Which of the following electronegativity order is incorrect?

(Memory Based JEE Mains 22/01/2025 ,Shift -1)

Number of elements from the following that CANNOT form compounds with valencies which match with their respective group valencies is

\(\mathrm{B},\mathrm{C},\mathrm{N},\mathrm{S},\mathrm{O},\mathrm{F},\mathrm{P},\mathrm{Al},\mathrm{Si}\)

[JEE Main 2024, 04 Apr (Shift 1)]

Number of elements from the following that CANNOT form compounds with valencies which match with their respective group valencies is

\(\mathrm{B},\mathrm{C},\mathrm{N},\mathrm{S},\mathrm{O},\mathrm{F},\mathrm{P},\mathrm{Al},\mathrm{Si}\)

[JEE Main 2024, 04 Apr (Shift 1)]

The incorrect decreasing order of atomic radii is:

Memory Based Question 28/Jan/25 Morning shift

Arrange the bonds in order of increasing ionic character in the molecules. \(LiF , K _2 O , N _2, SO _2\) and \(ClF _3\) :

[JEE Main 2024, 1 Feb (Shift 1)]

The atomic number of the element from the following with lowest \({1}^{\text{st }}\) ionisation enthalpy is :

[JEE Main 2025, 8 Apr (Shift 1)]

Given below are two statements :
Statement (I) : The radii of isoelectronic species increases in the order

\(M{g}^{2+}

Statement (II) : The magnitude of electron gain enthalpy of halogen decreases in the order, Cl>F>Br>I
In the light of the above statements, choose the most appropriate answer from the options given below:

Given below are two statements :
Statement (I) : The \(4 f\) and \(5 f\) - series of elements are placed separately in the Periodic table to preserve the principle of classification.

Statement (II) : s-block elements can be found in pure form in nature.
In the light of the above statements, choose the most appropriate answer from the options given below :

[JEE Main 2024, 27 Jan (Shift 1)]

Given below are two statements :
Statement (I) : The oxidation state of an element in a particular compound is the charge acquired by its atom on the basis of electron gain enthalpy consideration from other atoms in the molecule.

Statement (II) : \(\mathrm{p \pi}-\mathrm{p \pi}\) bond formation is more prevalent in second period elements over other periods.

In the light of the above statements, choose the most appropriate answer from the options given below :

[JEE Main 2024, 09 Apr (Shift 1)]

Given below are two statements :
Statement (I) : The oxidation state of an element in a particular compound is the charge acquired by its atom on the basis of electron gain enthalpy consideration from other atoms in the molecule.

Statement (II) : \(\mathrm{p \pi}-\mathrm{p \pi}\) bond formation is more prevalent in second period elements over other periods.

In the light of the above statements, choose the most appropriate answer from the options given below :

[JEE Main 2024, 09 Apr (Shift 1)]

Which of the following statements are NOT true about the periodic table?
A. The properties of elements are function of atomic weights.
B. The properties of elements are function of atomic numbers.
C. Elements having similar outer electronic configurations are arranged in same period.
D. An element's location reflects the quantum numbers of the last filled orbital.
E. The number of elements in a period is same as the number of atomic orbitals available in energy level that is
being filled.
Choose the correct answer from the options given below:

[JEE Main 2025, 24 Jan (Shift 1)]

Given below are two statements :
Statement (I) : The first ionization energy of Pb is greater than that of Sn .
Statement (II) : The first ionization energy of Ge is greater than that of Si .
In the light of the above statements, choose the correct answer from the options given below :

[JEE Main 2025, 24 Jan (Shift 2)]

Given below are two statements :
Statement (I) : The first ionization energy of Pb is greater than that of Sn .
Statement (II) : The first ionization energy of Ge is greater than that of Si .
In the light of the above statements, choose the correct answer from the options given below :

[JEE Main 2025, 24 Jan (Shift 2)]

Electronic configuration of four elements A, B, C and D are given below :
(A) \(1{\mathrm{s}}^{2}2{\mathrm{s}}^{2}2{\mathrm{p}}^{3}\)
(B) \(1{\mathrm{s}}^{2}2{\mathrm{s}}^{2}2{\mathrm{p}}^{4}\)
(C) \(1{\mathrm{s}}^{2}2{\mathrm{s}}^{2}2{\mathrm{p}}^{5}\)
(D) \(1{\mathrm{s}}^{2}2{\mathrm{s}}^{2}2{\mathrm{p}}^{2}\)
Which of the following is the correct order of increasing electronegativity (Pauling's scale)?

[JEE Main 2025, 2 Apr (Shift 2)]

Which of the following has maximum size :

\({\mathrm{Al}}^{3+},{\mathrm{Mg}}^{2+},{\mathrm{F}}^{-},{\mathrm{Na}}^{+}\)

(Memory Based JEE Mains 22/01/2025)

The correct orders among the following are
Atomic radius : \(\mathrm{B}<\mathrm{Al}<\mathrm{Ga}<\mathrm{In}<\mathrm{Tl}\)
Electronegativity : \(\mathrm{Al}<\mathrm{Ga}<\mathrm{In}<\mathrm{Tl}<\mathrm{B}\)
Density : \(\mathrm{Tl}<\mathrm{In}<\mathrm{Ga}<\mathrm{Al}<\mathrm{B}\)
1st Ionisation Energy : \(\mathrm{In}<\mathrm{Al}<\mathrm{Ga}<\mathrm{Tl}<\mathrm{B}\)
Choose the correct answer from the options given below

[JEE Main 2025, 3 Apr (Shift 2)]

The electron affinity value are negative for
A. \(\mathrm{Be}\to {\mathrm{Be}}^{-}\)
B. \(\mathrm{N}\to {\mathrm{N}}^{-}\)
C. \(\mathrm{O}\to {\mathrm{O}}^{2-}\)
D. \(\mathrm{Na}\to {\mathrm{Na}}^{-}\)
E. \(\mathrm{Al}\to {\mathrm{Al}}^{-}\)

Choose the most appropriate answer from the options given below :

[JEE Main 2024, 6 Apr (Shift 1)]

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:

[JEE Main 2024, 31 Jan (Shift 1)]

Given below are two statements:

Statement-I: The second ionisation enthalpy of Na is larger than the corresponding ionisation enthalpy of Mg.

Statement-II: The ionic radius of O^2– is larger than that of F^–. In the light of the above statements, choose the correct answer from the given below

[JEE Main 2026, 23 Jan (Shift 2)]

The statement(s) that are correct about the species

\({\mathrm{O}}^{2−},{\mathrm{F}}^{−},{\text{Na}}^{+}{\text{ and Mg}}^{2+}\)

(A) All are isoelectronic
(B) All have the same nuclear charge
(C) \({\mathrm{O}}^{2-}\) has the largest ionic radii
(D) \({\mathrm{Mg}}^{2+}\) has the smallest ionic radii

Choose the most appropriate answer from the options given below:

Which of the following statements are NOT true about the periodic table?
A. The properties of elements are function of atomic weights.
B. The properties of elements are function of atomic numbers.
C. Elements having similar outer electronic configurations are arranged in same period.
D. An element's location reflects the quantum numbers of the last filled orbital.
E. The number of elements in a period is same as the number of atomic orbitals available in energy level that is
being filled.
Choose the correct answer from the options given below:

[JEE Main 2025, 24 Jan (Shift 1)]

Arrange the bonds in order of increasing ionic character in the molecules. \(LiF , K _2 O , N _2, SO _2\) and \(ClF _3\) :

[JEE Main 2024, 1 Feb (Shift 1)]

In case of isoelectronic species the size of \(F ^{-}, Ne\) and \(Na ^{+}\)is affected by :

[JEE Main 2024, 1 Feb (Shift 1)]

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 answer from the options given below

[JEE Main 2024, 29 Jan (Shift 2)]

Which of the following electronegativity order is incorrect?

[JEE Main 2025, 22 Jan (Shift 1)]

Which of the following electronegativity order is incorrect?

[JEE Main 2025, 22 Jan (Shift 1)]

The ionic radii in (\({A}^{^\circ }\)) of \({N}^{3-},{O}^{2-}\)and \({F}^{-}\) are respectively.

The correct order of first ionization enthalpy values of the following elements is :
(A) \(\mathrm{O}\)
(B) \(\mathrm{N}\)
(C) \(\mathrm{Be}\)
(D) \(\mathrm{F}\)
(E) \(\mathrm{B}\)

Choose the correct answer from the options given below

[JEE Main 2024, 4 Apr (Shift 1)]

The successive 5 ionisation energies of an element are 800, 2427, 3658, 25024 and 32824 kJ/mol, respectively. By using the above values predict the group in which the above element is present :

[JEE Main 2025, 24 Jan (Shift 2)]

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

[JEE Main 2024, 4 Apr (Shift 2)]

Among the following oxides of p-block elements, number of oxides having amphoteric nature is \(Cl _2 O _7, CO , PbO _2, N _2 O , NO , Al _2 O _3, SiO _2, N _2 O _5, SnO _2\)

[JEE Main 2024, 1 Feb (Shift 1)]

Choose the incorrect trend in the atomic radii (r) of the elements

[JEE Main 2025, 7 Apr (Shift 2)]

Given below are two statements :
Statement (I) : According to the Law of Octaves, the elements were arranged in the increasing order of their atomic number.
Statement (II) : Meyer observed a periodically repeated pattern upon plotting physical properties of certain elements against their respective atomic numbers.
In the light of the above statements, choose the correct answer from the options given below:

[JEE Main 2025, 28 Jan (Shift 2)]

The electron affinity value are negative for
A. \(\mathrm{Be}\to {\mathrm{Be}}^{-}\)
B. \(\mathrm{N}\to {\mathrm{N}}^{-}\)
C. \(\mathrm{O}\to {\mathrm{O}}^{2-}\)
D. \(\mathrm{Na}\to {\mathrm{Na}}^{-}\)
E. \(\mathrm{Al}\to {\mathrm{Al}}^{-}\)

Choose the most appropriate answer from the options given below :

Given below are the pairs of group 13 elements showing their relation in terms of atomic radius.
\((\mathrm{B}<\mathrm{Al}),(\mathrm{Al}<\mathrm{Ga}),(\mathrm{Ga}<\mathrm{In})\mathrm{and}(\mathrm{In}<\mathrm{Tl})\)
Identify the elements present in the incorrect pair and in that pair find out the element (X) that has higher ionic radius \(({\mathrm{M}}^{3+})\) that the other one. The atomic number of the element (X) is

[JEE Main 2025, 4 Apr (Shift 1)]

Electronic configuration of four elements A, B, C and D are given below :
(A) \(1{\mathrm{s}}^{2}2{\mathrm{s}}^{2}2{\mathrm{p}}^{3}\)
(B) \(1{\mathrm{s}}^{2}2{\mathrm{s}}^{2}2{\mathrm{p}}^{4}\)
(C) \(1{\mathrm{s}}^{2}2{\mathrm{s}}^{2}2{\mathrm{p}}^{5}\)
(D) \(1{\mathrm{s}}^{2}2{\mathrm{s}}^{2}2{\mathrm{p}}^{2}\)
Which of the following is the correct order of increasing electronegativity (Pauling's scale)?

[JEE Main 2025, 2 Apr (Shift 2)]

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:

[JEE Main 2024, 31 Jan (Shift 1)]

The correct order of first ionization enthalpy values of the following elements is:

(A) O (B) N (C) Be (D) F (E) B

Choose the correct answer from the options given below:

The ionic radii in (\({A}^{^\circ }\)) of \({N}^{3-},{O}^{2-}\)and \({F}^{-}\) are respectively.

Given below are two statements :
Statement (I) : According to the Law of Octaves, the elements were arranged in the increasing order of their atomic number.
Statement (II) : Meyer observed a periodically repeated pattern upon plotting physical properties of certain elements against their respective atomic numbers.
In the light of the above statements, choose the correct answer from the options given below:

In period 4 of the periodic table, the elements with highest and lowest atomic radii are respectively.

[JEE Main 2026, 28 Jan (Shift 1)]

The element that does not belong to the same period of the remaining elements (modern periodic table) is:

[JEE Main 2025, 23 Jan (Shift 1)]

Given below are the pairs of group 13 elements showing their relation in terms of atomic radius.
\((\mathrm{B}<\mathrm{Al}),(\mathrm{Al}<\mathrm{Ga}),(\mathrm{Ga}<\mathrm{In})\mathrm{and}(\mathrm{In}<\mathrm{Tl})\)
Identify the elements present in the incorrect pair and in that pair find out the element (X) that has higher ionic radius \(({\mathrm{M}}^{3+})\) that the other one. The atomic number of the element (X) is

[JEE Main 2025, 4 Apr (Shift 1)]

Given below are two statements :

Statement (I): An element in the extreme left of the periodic table forms acidic oxides.

Statement (II) : Acid is formed during the reaction between water and oxide of a reactive element present in the extreme right of the periodic table.

In the light of the above statements, choose the correct answer from the options given below.

[JEE Main 2025, 22 Jan (Shift 2)]

In case of isoelectronic species the size of \(F ^{-}, Ne\) and \(Na ^{+}\)is affected by :

[JEE Main 2024, 1 Feb (Shift 1)]

The correct decreasing order of electronegativity is:

(Memory Based JEE Mains 22/01/2025 Shift-1)

The type of oxide formed by the element among Li , Na , Be , Mg , B and Al that has the least atomic radius is:

[JEE Main 2025, 29 Jan (Shift 2)]

Arrange the bonds in order of increasing ionic character in the molecules. \(LiF , K _2 O , N _2, SO _2\) and \(ClF _3\) :

[JEE Main 2024, 1 Feb (Shift 1)]

The successive 5 ionisation energies of an element are 800, 2427, 3658, 25024 and 32824 kJ/mol, respectively. By using the above values predict the group in which the above element is present :

Consider the elemetns N, P, O, S, Cl and F. The number of valence electrons present in the elements with most and least metallic character from the above list is respectively.

[JEE Main 2026, 28 Jan (Shift 2)]

The element that does not belong to the same period of the remaining elements (modern periodic table) is:

[JEE Main 2025, 23 Jan (Shift 1)]

In period 4 of the periodic table, the elements with highest and lowest atomic radii are respectively.

[JEE Main 2026, 28 Jan (Shift 1)]

The atomic number of the element from the following with lowest \({1}^{\text{st }}\) ionisation enthalpy is :

[JEE Main 2025, 8 Apr (Shift 1)]

The correct order of first ionization enthalpy values of the following elements is :
(A) \(\mathrm{O}\)
(B) \(\mathrm{N}\)
(C) \(\mathrm{Be}\)
(D) \(\mathrm{F}\)
(E) \(\mathrm{B}\)

Choose the correct answer from the options given below

[JEE Main 2024, 4 Apr (Shift 1)]

The incorrect decreasing order of atomic radii is:

Memory Based Question 28/Jan/25 Morning shift

Arrange the bonds in order of increasing ionic character in the molecules. \(LiF , K _2 O , N _2, SO _2\) and \(ClF _3\) :

[JEE Main 2024, 1 Feb (Shift 1)]

Select the incorrect statement about modern periodic table (memory based jee mains shift-1 24/01/2025)

The incorrect decreasing order of atomic radii is

[JEE Main 2025, 28 Jan (Shift 1)]

Given below are two statements :
Statement (I) : The radii of isoelectronic species increases in the order

\(M{g}^{2+}

Statement (II) : The magnitude of electron gain enthalpy of halogen decreases in the order, Cl>F>Br>I
In the light of the above statements, choose the most appropriate answer from the options given below:

[JEE Main 2025, 29 Jan (Shift 1)]

Given below are two statements:

Statement-I: The second ionisation enthalpy of Na is larger than the corresponding ionisation enthalpy of Mg.

Statement-II: The ionic radius of O^2– is larger than that of F^–. In the light of the above statements, choose the correct answer from the given below

[JEE Main 2026, 23 Jan (Shift 2)]

Statement -1: Correct order of ionic radius for \({\mathrm{Mg}}^{2+},{\mathrm{Na}}^{+},{\mathrm{O}}^{2-}\mathrm{and}{\mathrm{F}}^{-}\) is \({\mathrm{F}}^{-}>{\mathrm{O}}^{2-}>{\mathrm{Na}}^{+}>{\mathrm{Mg}}^{2+}\)

Statement -2: The correct order of magnitude of electron gain enthalpy for the 17th group follows the order Cl>F>Br >I (Magnitude only )

(Memory based 29 Jan /2025 morning shift )

Which of the following electronegativity order is incorrect?

(Memory Based JEE Mains 22/01/2025 ,Shift -1)

Given below are two statements :

Statement (I): An element in the extreme left of the periodic table forms acidic oxides.

Statement (II) : Acid is formed during the reaction between water and oxide of a reactive element present in the extreme right of the periodic table.

In the light of the above statements, choose the correct answer from the options given below

Choose the incorrect trend in the atomic radii (r) of the elements

[JEE Main 2025, 7 Apr (Shift 2)]

The element having the highest first ionization enthalpy is

[JEE Main 2024, 29 Jan (Shift 2)]

Which of the following electronegativity order is incorrect?

(Memory Based JEE Mains 22/01/2025 ,Shift -1)

The statement(s) that are correct about the species

\({\mathrm{O}}^{2−},{\mathrm{F}}^{−},{\text{Na}}^{+}{\text{ and Mg}}^{2+}\)

(A) All are isoelectronic
(B) All have the same nuclear charge
(C) \({\mathrm{O}}^{2-}\) has the largest ionic radii
(D) \({\mathrm{Mg}}^{2+}\) has the smallest ionic radii

Choose the most appropriate answer from the options given below:

The type of oxide formed by the element among Li , Na , Be , Mg , B and Al that has the least atomic radius is:

[JEE Main 2025, 29 Jan (Shift 2)]

An element ' E ' has the ionisation enthalpy value of \(374kJmo{l}^{-1}\). ' E ' reacts with elements A, B, C and D with electron gain enthalpy values of -328,-349,-325 and \(-295kJmo{l}^{-1}\), respectively. The correct order of the products EA, EB, EC and ED in terms of ionic character is :

Given below are two statements

Statement-I: A plot of \(\sqrt{\mathrm{v}}\) (v = frequency of X-rays emitted) Vs atomic mass is a straight line

Statement-II: A plot of v (v = frequency of X-rays emitted) Vs atomic number is a straight line

In the light of above statements, choose the correct answer from the options given below

[JEE Main 2025, 23 Jan (Shift 2)]

Given below are two statements:
Statement - I: Along the period, the chemical reactivity of the elements gradually increases from group 1 to group 18 .
Statement - II: The nature of oxides formed by group 1 elements is basic while that of group 17 elements is acidic.
In the light of the above statements, choose the most appropriate from the options given below:

[JEE Main 2024, 30 Jan (Shift 2)]

Which of the following statements are correct?
A. The process of the addition of an electron to a neutral gaseous atom is always exothermic
B. The process of removing an electron from an isolated gaseous atom is always endothermic
C. The \({1}^{\text{st }}\) ionization energy of the boron is less than that of the beryllium
D. The electronegativity of C is 2.5 in \({\mathrm{CH}}_{4}\) and \({\mathrm{CCl}}_{4}\)
E. Li is the most electropositive among elements of group I
Choose the correct answer from the options gives below

[JEE Main 2025, 3 Apr (Shift 1)]

Consider the elemetns N, P, O, S, Cl and F. The number of valence electrons present in the elements with most and least metallic character from the above list is respectively.

[JEE Main 2026, 28 Jan (Shift 2)]

Consider the elemetns N, P, O, S, Cl and F. The number of valence electrons present in the elements with most and least metallic character from the above list is respectively.

[JEE Main 2026, 28 Jan (Shift 2)]

Given below are two statements :
Statement (I) : The first ionisation enthalpy of group 14 elements is higher than the corresponding elements of group 13.
Statement (II) : Melting points and boiling points of group 13 elements are in general much higher than those the corresponding elements of group 14 .
In the light of the above statements, choose the most appropriate answer from the options given below :

[JEE Main 2025, 4 Apr (Shift 2)]

The correct order of first ionization enthalpy values of the following elements is:

(A) O (B) N (C) Be (D) F (E) B

Choose the correct answer from the options given below:

Given below are two statements

Statement I: K > Mg > Al > B is the correct order in terms of metallic character.

Statement II: Atomic radius is always greater than the ionic radius for any element. In the light of the above statements, choose the correct answer from the options given below

[JEE Main 2026, 24 Jan (Shift 1)]

An element ' E ' has the ionisation enthalpy value of \(374kJmo{l}^{-1}\). ' E ' reacts with elements A, B, C and D with electron gain enthalpy values of -328,-349,-325 and \(-295kJmo{l}^{-1}\), respectively. The correct order of the products EA, EB, EC and ED in terms of ionic character is :

[JEE Main 2025, 29 Jan (Shift 1)]

If IUPAC name of an element is "Unununnium" then the element belongs to \({n}^{\text {th }}\) group of Periodic table. The value of \(n\) is.........

[JEE Main 2024, 30 Jan (Shift 1)]

Which of the following statements are correct?
A. The process of the addition of an electron to a neutral gaseous atom is always exothermic
B. The process of removing an electron from an isolated gaseous atom is always endothermic
C. The \({1}^{\text{st }}\) ionization energy of the boron is less than that of the beryllium
D. The electronegativity of C is 2.5 in \({\mathrm{CH}}_{4}\) and \({\mathrm{CCl}}_{4}\)
E. Li is the most electropositive among elements of group I
Choose the correct answer from the options gives below

[JEE Main 2025, 3 Apr (Shift 1)]

Statement -1: Correct order of ionic radius for \({\mathrm{Mg}}^{2+},{\mathrm{Na}}^{+},{\mathrm{O}}^{2-}\mathrm{and}{\mathrm{F}}^{-}\) is \({\mathrm{F}}^{-}>{\mathrm{O}}^{2-}>{\mathrm{Na}}^{+}>{\mathrm{Mg}}^{2+}\)

Statement -2: The correct order of magnitude of electron gain enthalpy for the 17th group follows the order Cl>F>Br >I (Magnitude only )

(Memory based 29 Jan /2025 morning shift )

The element having the highest first ionization enthalpy is

[JEE Main 2024, 29 Jan (Shift 2)]

Given below are two statements :
Statement (I) : Both metals and non-metals exist in p and d-block elements.
Statement (II) : Non-metals have higher ionisation enthalpy and higher electronegativity than the metals.

In the light of the above statements, choose the most appropriate answer from the options given below:

EndFragment [JEE Main 2024, 01 Feb (Shift 2)]

Given below are two statements :
Statement (I) : Both metals and non-metals exist in p and d-block elements.
Statement (II) : Non-metals have higher ionisation enthalpy and higher electronegativity than the metals.

In the light of the above statements, choose the most appropriate answer from the options given below:

EndFragment [JEE Main 2024, 01 Feb (Shift 2)]

The incorrect decreasing order of atomic radii is

[JEE Main 2025, 28 Jan (Shift 1)]

The acidic, basic and amphoteric oxides, respectively, are:

For elements B, C, N, Li, Be, O and F the correct order of first ionization enthalpy is [JEE Main 2023, 11 Apr (Shift 1)]

Elements X, Y and Z are located in the 3rd period. Their oxides are, respectively, basic, amphoteric and acidic. Which of the following represents the correct ordering of their atomic numbers?

The five successive ionization energies of an element are 800, 2427, 3658, 25024 and 32824 kJmol^-1 respectively. The number of valence electrons is:

[JEE Main 2025, 24 Jan (Shift 2)]

Among the statements (I - IV), the correct ones are

(I) \(\mathrm{Be}\) has smaller atomic radius compared to \( \mathrm{Mg} \).

(II) \(\mathrm{Be}\) has higher ionization enthalpy than \( \mathrm{Al} \).

(III) Charge/radius ratio of \( \mathrm{Be} \) is greater than that of \( \mathrm{Al} \).

(IV) Both \( \mathrm{Be} \) and \( \mathrm{Al} \) form mainly covalent compounds.

The increasing order of the atomic radii of following elements is :

(a) \( \mathrm{C} \) (b) \( \mathrm{O} \) (c) \( \mathrm{F} \) (d) \( \mathrm{Cl} \) (e) \( \mathrm{Br} \)

[JEE Main 2020, 8 Jan (Shift 2)]

The reducing property of alkali metals follows the order

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

[JEE Main 2021, 17 Mar (Shift 2)]

Which of the following represents the correct order of metallic character of the given elements? [JEE Main 2023, 25 Jan (Shift 2)]

The number of s-electrons present in an ion with 55 protons in its unipositive state is

[JEE Main 2023, 24 Jan (Shift 2)]

Which of the following oxides are Acidic, Basic and amphoteric respectively?

Outermost electronic configuration of a group \( 13^{\text {th }} \) element \( E \) is \( 4 s^{2} 4 p^{1} \). The electronic configuration of an element of p-block, period-five placed diagonally to element \( \mathrm{E} \) is:

[JEE Main 2021, 20 Jul (Shift 2)]

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

[JEE Main 2021, 16 Mar (Shift 2)]

Assertion(A): Element oxide from left of the periodic table are acidic in nature.

Reason (R) :Element oxide from right of the periodic table on hydrolysis gives
acid.

(Memory Based JEE Mains 22/01/2025 Shift -2)

Total number of acidic oxides among \({\mathrm{N}}_{2}{\mathrm{O}}_{3},\text{ }{\mathrm{NO}}_{2},\text{ }{\mathrm{N}}_{2}\mathrm{O},\text{ }{\mathrm{Cl}}_{2}{\mathrm{O}}_{7},\text{ }{\mathrm{SO}}_{2},\text{ }\mathrm{CO},\text{ }\mathrm{CaO},\text{ }{\mathrm{Na}}_{2}\mathrm{O}\) and NO is

[JEE Main 2023, 29 Jan (Shift 2)]

The correct order of acidic strength

Given below are two statements:

Statement-I: Both metal and non-metal exist in p and d-block elements.

Statement-II: Non-metals have higher ionisation enthalpy and higher electronegativity than the metals.

In the light of the above statements, choose the most appropriate answer from the option given below:

Given below are two statements. One is labelled as Assertion A and the other is labelled as Reasons R.
Assertion (A) : The first ionization enthalpy for oxygen is lower than that of nitrogen
Reason (R) : The four electrons in \(2 p\) orbitals of oxygen experience more electron electron repulsion.
In the light of the above statements, choose the correct answer from the options given below

[JEE Main 2022, 29 Jun (Shift 2)]

The process that is NOT endothermic in nature is

[JEE Main 2020, 4 Sep (Shift 2)]

The correct increasing order of the ionic radii is

[JEE Main 2023, 31 Jan (Shift 1)]

For the elements B, C, N, Li, Be, O and F, which of the following represents the correct order of their first ionization enthalpies (in ascending order)?

Which one of the following sets of ions represents a collection of isoelectronic species?

(Given: Atomic Number: \(\mathrm{F}:9,\mathrm{Cl}:17,\mathrm{Na}=11,\mathrm{Mg}=12\),\(\mathrm{Al}=13,\mathrm{K}=19,\mathrm{Ca}=20,\mathrm{Sc}=21\) )

[JEE Main 2023, 1 Feb (Shift 2)]

Which one of the following elements will remain as liquid inside pure boiling water?

[JEE Main 2023, 6 Apr (Shift 2)]

Match the Column I and Column II and choose the correct option:

The correct increasing order of the ionic radii is

Statement-I: The decrease in first ionization enthalpy from B to AI is much larger than that from AI 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 options given below [JEE Main 2023, 29 Jan (Shift 2)]

The first ionization energies (in kJ mol⁻¹) of Na, Mg, Al and Si respectively are:

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 above statements, choose the most appropriate from the options given below:

Match List-I with List-II.

Choose the correct answer from the options given below:

Given below are two statements:

Statement-I: Fluorine has the most negative electron gain enthalpy in its group.

Statement-II: Oxygen has the least negative electron gain enthalpy in its group.

In the light of the above statements, choose the most appropriate answer from the options given below:

[JEE Main 2024, 29 Jan (Shift 2)]

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

[JEE Main 2021, 27 Aug (Shift 2)]

The correct order of metallic character is:

For which pair of elements will the difference in electron gain enthalpies be the greatest?

For electron gain enthalpies of the elements (denoted as Δ_eg H), which of the following statements is incorrect?

Inert gases have positive electron gain enthalpy. Which of the following represents the correct order of increasing electron gain enthalpy for the given noble gases?

Among the statements (I–IV) about Be and Al, the correct ones are:

(I) Be has smaller atomic radius compared to Mg.

(II) Be has higher first ionization enthalpy than Al.

(III) Charge/radius ratio of Be (as Be²⁺) is greater than that of Al (as Al³⁺).

(IV) Both Be and Al form mainly covalent compounds.

Arrange the elements P, At, C and Br in order of increasing electronegativity.

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 carry more charge than \({\mathrm{Mg}}^{+}\).

In the light of the above statements, choose the correct answer from the options given below:

[JEE Main 2023, 10 Apr (Shift 2)]

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

[JEE Main 2021, 22 Jul (Shift 2)]

Number of amphoteric compounds among the following is:

(A) BeO

(B) BaO

(C) Be(OH)₂

(D) Sr(OH)₂

[JEE Main 2021, 24 Feb (Shift 1)]

Consider the elements \( \mathrm{Mg}, \mathrm{Al}, \mathrm{S}, \mathrm{P} \) and \( \mathrm{Si} \), the correct increasing order of their first ionization enthalpy is

[JEE Main 2021, 24 Feb (Shift 1)]

When characteristic X⁻ray frequencies ν of elements are plotted as νⁿ versus atomic number Z, the graph is linear. Using Moseley's law which states ν \(\propto\) (Z − σ)² for a series, what is the value of n that makes ν^n proportional to Z?

Given below are two statements:

Statement-I: Fluorine has the most negative electron gain enthalpy in its group.

Statement-II: Oxygen has the least negative electron gain enthalpy in its group.

In the light of the above statements, choose the most appropriate answer from the options given below:

B has a smaller first ionization enthalpy than Be. Consider the following statements:

(I) It is easier to remove a 2p electron than a 2s electron.

(II) The 2p electron of B is more shielded from the nucleus by the inner core electrons than the 2s electrons of Be.

(III) A 2s electron has greater penetration power than a 2p electron.

(IV) Atomic radius of B is more than Be (atomic number B = 5, Be = 4).

Which of the above statements are correct?

The first ionization energy (in \( \mathrm{kJ} / \mathrm{mol} \) ) of \( \mathrm{Na}, \mathrm{Mg}, \mathrm{Al} \) and Si respectively, are

[JEE Main 2020, 8 Jan (Shift 1)]

The first ionization energy (in \( \mathrm{kJ} / \mathrm{mol} \) ) of \( \mathrm{Na}, \mathrm{Mg}, \mathrm{Al} \) and Si respectively, are

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 light above statements, choose the most appropriate from the questions given below:

[JEE Main 2024, 30 Jan (Shift 2)]

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

[JEE Main 2023, 1 Feb (Shift 2)]

The first ionization energy of magnesium is smaller as compound to that of elements \( \mathrm{X} \) and \( \mathrm{Y} \) but higher than that of Z. The elements X, Y and \( \mathrm{Z} \), respectively are:

[JEE Main 2021, 18 Mar (Shift 2)]