jee main chemistry important questions | Classification Of Elements And Periodicity In Properties

Q 1 :

Consider the following elements.

$Group ↓_{C' D'}^{A' B' \to Period}$

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 answer from the options given below: [2024]

B, C and D only
A and B only
A, B and D only
A only

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(3)

Atomic and metallic radii decreases from left to right across a period and increase down the group. The same trend is followed by metallic character.

Q 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: [2024]

Both Statement I and Statement II are false
Both Statement I and Statement II are true
Statement I is false but Statement II is true
Statement I is true but Statement II is false

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(3)

Statement (I): s, d, and f block has only metals while p block has metals, non-metals and metalloids. Thus statement (I) is false.

Statement (II): Non-metals are electronegative i.e. have a tendency to attract electrons. Statement (II) is true.

Q 3 :

Given below are two statements:

Statement I: The metallic radius of Na is 1.86 A° and the ionic radius of ${Na}^{+}$ is lesser than 1.86 A°.

Statement II: Ions are always smaller in size than the corresponding elements.

In the light of the above statements, choose the correct answer from the options given below : [2024]

Statement I is correct but Statement II is false
Both Statement I and Statement II are false
Both Statement I and Statement II are true
Statement I is incorrect but Statement II is true

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(1)

Cations are formed by losing electrons hence are smaller than parent atom. Anions are formed by gaining electrons hence are larger than parent atom.

Q 4 :

Match List I with List II.

List I List II

A. Melting Point [K] I. $Tl > \ln > Ga > Al > B$

B. Ionic Radius [ $M^{+ 3} / pm$ ] II. $B > Tl > Al \approx Ga > \ln$

C. $∆_{i} H_{1} [kJ$ ${mol}^{- 1}]$ III. $Tl > In > Al > Ga > B$

D. Atomic Radius [pm] IV. $B > Al > Tl > In > Ga$

Choose the correct answer from the options given below: [2024]

A-IV, B-I, C-II, D-III
A-II, B-III, C-IV, D-I
A-III, B-IV, C-I, D-II
A-I, B-II, C-III, D-IV

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(1)

A.

Element	B	$Al$	Ga	$In$	$Tl$
Melting point (K)	2453 (Unusually high)	933	303 (liquid in summers)	430	576

Order of melting point is : $B > Al > Tl > In > Ga$ .

B. Ionic radius increases down the group due to increase in number of shells. Order of ionic radius is: $Tl > In > Ga > Al > B$ .

C. Ionization energy decreases down the group. But Ga and Tl have ionization energy more than expected value because of poor shielding of d and f electrons respectively. Order of ionization energy is : $B > Tl > Ga > Al > In$

D. Atomic radius increases down the group due to increase in number of shells but Ga is smaller than Al due to poor shielding of d electrons.

Element	B	$Al$	Ga	$In$	$Tl$
Atomic radius (pm)	88	143	135	167	170

Order of atomic radius is: $Tl > In > Al > Ga > B$ .

Q 5 :

The statement(s) that are correct about the species $O^{2 -}$ , $F^{-}$ , ${Na}^{+}$ and ${Mg}^{2 +} .$

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

Choose the most appropriate answer from the options given below: [2024]

(A), (B), (C) and (D)
(B), (C) and (D) only
(A), (C) and (D) only
(C) and (D) only

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(3)

For isoelectronic species, more are number of protons, more is effective nuclear charge hence smaller is the size.

Q 6 :

The incorrect decreasing order of atomic radii is [2025]

Mg > Al > C > O
Be > Mg > Al > Si
Al > B > N > F
Si > P > Cl > F

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(2)

Radius increases down the group because of more number of shells, hence radius of Mg is more than that of Be.

Q 7 :

The type of oxide formed by the element among Li, Na, Be, Mg, B and Al that has the least atomic radius is : [2025]

$A_{2} O$
$AO$
$A_{2} O_{3}$
${AO}_{2}$

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(3)

Q 8 :

Choose the incorrect trend in the atomic radii (r) of the elements : [2025]

$r_{Br} < r_{K t}$
$r_{Mg} < r_{Al}$
$r_{Rb} < r_{Cs}$
$r_{At} < r_{Cs}$

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(2)

From left to right across a period, atomic radius decreases, so $r_{Al} < r_{Mg}$ .

Q 9 :

The correct order of hydration enthalpies is

(A) $K^{+}$ (B) ${Rb}^{+}$ (C) ${Mg}^{2 +}$ (D) ${Cs}^{+}$ (E) ${Ca}^{2 +}$

Choose the correct answer from the options given below: [2023]

C > E > A > B > D
C > E > A > D > B
C > A > E > B > D
E > C > A > B > D

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(1)

${Mg}^{2 +} > {Ca}^{2 +} > K^{+} > {Rb}^{+} > {Cs}^{+}$

Decreasing the size, hydration energy increases.

Q 10 :

The correct increasing order of the ionic radii is [2023]

${Ca}^{2 +} < K^{+} < {Cl}^{-} < S^{2 -}$
$S^{2 -} < {Cl}^{-} < {Ca}^{2 +} < K^{+}$
$K^{+} < S^{2 -} < {Ca}^{2 +} < {Cl}^{-}$
${Cl}^{-} < {Ca}^{2 +} < K^{+} < S^{2 -}$

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(1)

The correct increasing order of size is ${Ca}^{2 +} < K^{+} < {Cl}^{-} < S^{2 -}$

Q 11 :

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

(Given: Atomic Number: F : 9, Cl : 17, Na = 11, Mg = 12, Al = 13, K = 19, Ca = 20, Sc = 21) [2023]

$N^{3 -}, O^{2 -}, F^{-}, S^{2 -}$
${Li}^{+}, {Na}^{+}, {Mg}^{2 +}, {Ca}^{2 +}$
${Ba}^{2 +}, {Sr}^{2 +}, K^{+}, {Ca}^{2 +}$
$K^{+}, {Cl}^{-}, {Ca}^{2 +}, {Sc}^{3 +}$

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(4)

${Ca}^{+ 2}, K^{+}, {Sc}^{3 +}, {Cl}^{-}$ contain same no. of electrons, i.e. 18.

Hence they are iso-electronic species.

Q 12 :

The total number of isoelectronic species from the given set is ________.

$O^{2 -}, F^{-}, Al, {Mg}^{2 +}, {Na}^{+}, O^{+}, Mg, {Al}^{3 +}, F$ [2023]

(5)

Species:	$O^{2 -}$	$F^{-}$	$Al$	${Mg}^{2 +}$	${Na}^{+}$	$O^{+}$	$Mg$	${Al}^{3 +}$	$F$
No. of electron	10	10	13	10	10	7	12	10	9

Q 13 :

The correct orders among the following are: [2025]

A. Atomic radius : B < Al < Ga < In < Tl

B. Electronegativity : Al < Ga < In < Tl < B

C. Density : Tl < In < Ga < Al < B

D. 1st Ionisation Energy : In < Al < Ga < Tl < B

Choose the correct answer from the options given below:

B and D Only
A and C Only
C and D Only
A and B Only

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(1)

Q 14 :

Given below are two statements: [2025]

Statement I : Nitrogen forms oxides with +1 to +5 oxidation states due to the formation of $p π - p π$ bond with oxygen.

Statement II : Nitrogen does not form halides with +5 oxidation state due to the absence of d-orbital in it.

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

Statement I is true but Statement II is false
Both Statement I and Statement II are false
Statement I is false but Statement II is true
Both Statement I and Statement II are true

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(4)

Q 15 :

Given below are the pairs of group 13 elements showing their relation in terms of atomic radius.

$(B < Al), (Al < Ga), (Ga < In) and (In < Tl)$

Identify the elements present in the incorrect pair and in that pair find out the element (X) that has higher ionic radius $(M^{3 +})$ that the other one. The atomic number of the element (X) is [2025]

31
49
13
81

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(1)

Q 16 :

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: [2026]

Both Statement I and Statement II are false
Statement I is true but Statement II is false
Statement I is false but Statement II is true
Both Statement I and Statement II are true

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(2)

Metallic character of s-block elements is greater than p-block elements.

Anionic radius is greater than atomic radius but cationic radius is always less than atomic radius for any element.

Q 17 :

Which of the following represents the correct trend for the mentioned property ?

A. F > P > S > B

First Ionization Energy

B. Cl > F > S > P

Electron Affinity

C. K > Al > Mg > B

Metallic character

D. $K_{2} O > {Na}_{2} O > MgO > {Al}_{2} O_{3}$

Basic character

Choose the correct answer from the options given below : [2026]

A and B only
B and C only
A, B and D only
A, B, C and D

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⇒ On moving left to right in a period IE increases and from top to bottom in a group IE decreases.

F > P > S > B (IE order)

⇒ On moving left to right in a period metallic and basic character decreases.

K > Mg > Al > B (Metallic character order)

⇒ On moving top to bottom in a group metallic and basic character increases.

$K_{2} O > {Na}_{2} O > MgO > {Al}_{2} O_{3}$

⇒ EA : Group 17 > Group 16 > Group 15

Cl > F > S > P

Q 18 :

Given below are two statements: [2026]

Statement I: The halogen that makes the longest bond with hydrogen in HX, has the smallest covalent radius in its group.

Statement II: A group 15 element’s hydride ${EH}_{3}$ has the lowest boiling point among corresponding hydrides of other group 15 elements. The maximum covalency of that element E is 4.

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

Both Statement I and Statement II are true
Statement I is true but Statement II is false
Both Statement I and Statement II are false
Statement I is false but Statement II is true

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(3)

$HF < HCl < HBr < HI (bond length order)$

$F < Cl < Br < I (radius order)$

${PH}_{3} < {AsH}_{3} < {NH}_{3} < {SbH}_{3} < {BiH}_{3} (Boiling point order)$

$Maximum possible covalency of phosphorus is 6$

Q 19 :

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 options given below: [2026]

Both Statement I and Statement II are false
Both Statement I and Statement II are true
Statement I is false but Statement II is true
Statement I is true but Statement II is false

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(2)

${Na}^{+} : 1 s^{2} 2 s^{2} 2 p^{6} (fully filled electronic configuration)$

${Mg}^{+} : 1 s^{2} 2 s^{2} 2 p^{6} 3 s^{1}$

${IE}_{2} of Na > {IE}_{2} of Mg$

$Size of O^{2 -} > F^{-}$

Q 20 :

Given below are two statements :

Statement I : The correct order in terms of atomic/ionic radii is $Al > Mg > {Mg}^{2 +} > {Al}^{3 +}$ .

Statement II : The correct order in terms of the magnitude of electron gain enthalpy is $C l > B r > S > O$

In the light of the above statements, choose the correct answer from the options given below : [2026]

Both Statement I and Statement II are true
Statement I is true but Statement II is false
Statement I is false but Statement II is true
Both Statement I and Statement II are false

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(3)

$Correct order of size is Mg > Al > {Mg}^{2 +} > {Al}^{3 +}$

$Atomic size depends mainly upon Z_{effective} and shell number.$

$Generally on moving down the group electron affinity decreases$

$and on moving across the period electron affinity increases.$

$In the periodic table Cl has maximum electron affinity.$

$Halogen has higher electron affinity than Chalcogen.$

$Cl > Br > S > O$

Q 21 :

The correct increasing order of C–H (A), C–O (B), C=O (C) and C≡N (D) bonds in terms of covalent bond length is : [2026]

D < C < A < B
D < C < B < A
A < B < C < D
A < D < C < B

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(4)

$C - H (A) 107 pm$

$C \equiv N (D) 116 pm$

$C - O (B) 143 pm$

$C = O (C) 121 pm$

Q 22 :

In period 4 of the periodic table, the elements with highest and lowest atomic radii are respectively: [2026]

K & Se
Rb & Br
Na & Cl
K & Br

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(4)

In a period moving from left to right atomic size decreases.

Q 23 :

Consider the following statement:

(i) Atomic radii decreases across a row of the periodic table when we move from left to right

(ii) Atomic radii increases down the column as we move from top to bottom

(iii) Screening effect order $s > p > d > f$

Correct statements are

(i) and (ii) only
(i) and (iii) only
(ii) and (iii) only
(i), (ii) and (iii)

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(4)

periodic property

Topic Question Set

Q 6 :

The incorrect decreasing order of atomic radii is [2025]

Q 7 :

The type of oxide formed by the element among Li, Na, Be, Mg, B and Al that has the least atomic radius is : [2025]

Q 8 :

Choose the incorrect trend in the atomic radii (r) of the elements : [2025]

Q 9 :

The correct order of hydration enthalpies is

(A) $K^{+}$ (B) ${Rb}^{+}$ (C) ${Mg}^{2 +}$ (D) ${Cs}^{+}$ (E) ${Ca}^{2 +}$

Choose the correct answer from the options given below: [2023]

Q 10 :

The correct increasing order of the ionic radii is [2023]

Q 11 :

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

(Given: Atomic Number: F : 9, Cl : 17, Na = 11, Mg = 12, Al = 13, K = 19, Ca = 20, Sc = 21) [2023]

Q 12 :

The total number of isoelectronic species from the given set is ________.

$O^{2 -}, F^{-}, Al, {Mg}^{2 +}, {Na}^{+}, O^{+}, Mg, {Al}^{3 +}, F$ [2023]

Q 13 :

The correct orders among the following are: [2025]

A. Atomic radius : B < Al < Ga < In < Tl

B. Electronegativity : Al < Ga < In < Tl < B

C. Density : Tl < In < Ga < Al < B

D. 1st Ionisation Energy : In < Al < Ga < Tl < B

Choose the correct answer from the options given below:

(1)

(4)

(1)

Q 21 :

The correct increasing order of C–H (A), C–O (B), C=O (C) and C≡N (D) bonds in terms of covalent bond length is : [2026]

Q 22 :

In period 4 of the periodic table, the elements with highest and lowest atomic radii are respectively: [2026]

Q 23 :

Consider the following statement:

(i) Atomic radii decreases across a row of the periodic table when we move from left to right

(ii) Atomic radii increases down the column as we move from top to bottom

(iii) Screening effect order $s > p > d > f$

Correct statements are

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	List I		List II
A.	Melting Point [K]	I.	$Tl > \ln > Ga > Al > B$
B.	Ionic Radius [ $M^{+ 3} / pm$ ]	II.	$B > Tl > Al \approx Ga > \ln$
C.	$∆_{i} H_{1} [kJ$ ${mol}^{- 1}]$	III.	$Tl > In > Al > Ga > B$
D.	Atomic Radius [pm]	IV.	$B > Al > Tl > In > Ga$

A. F > P > S > B	First Ionization Energy
B. Cl > F > S > P	Electron Affinity
C. K > Al > Mg > B	Metallic character
D. $K_{2} O > {Na}_{2} O > MgO > {Al}_{2} O_{3}$	Basic character

Topic Question Set

Q 4 : Match List I with List II. List I List II A. Melting Point [K] I. Tl>ln>Ga>Al>B B. Ionic Radius [M+3/pm] II. B>Tl>Al≈Ga>ln C. ∆iH1[kJ mol-1] III. Tl>In>Al>Ga>B D. Atomic Radius [pm] IV. B>Al>Tl>In>Ga Choose the correct answer from the options given below: [2024]

Q 5 : The statement(s) that are correct about the species O2-, F-, Na+ and Mg2+. (A) All are isoelectronic (B) All have the same nuclear charge (C) O2- has the largest ionic radii (D) Mg2+ has the smallest ionic radii Choose the most appropriate answer from the options given below: [2024]

Q 6 : The incorrect decreasing order of atomic radii is [2025]

Q 7 : The type of oxide formed by the element among Li, Na, Be, Mg, B and Al that has the least atomic radius is : [2025]

Q 8 : Choose the incorrect trend in the atomic radii (r) of the elements : [2025]

Q 9 : The correct order of hydration enthalpies is (A) K+ (B) Rb+ (C) Mg2+ (D) Cs+ (E) Ca2+ Choose the correct answer from the options given below: [2023]

Q 10 : The correct increasing order of the ionic radii is [2023]

Q 11 : Which one of the following sets of ions represents a collection of isoelectronic species? (Given: Atomic Number: F : 9, Cl : 17, Na = 11, Mg = 12, Al = 13, K = 19, Ca = 20, Sc = 21) [2023]

Q 12 : The total number of isoelectronic species from the given set is ________. O2-,F-,Al,Mg2+,Na+,O+,Mg,Al3+,F [2023]

Q 13 : The correct orders among the following are: [2025] A. Atomic radius : B < Al < Ga < In < Tl B. Electronegativity : Al < Ga < In < Tl < B C. Density : Tl < In < Ga < Al < B D. 1st Ionisation Energy : In < Al < Ga < Tl < B Choose the correct answer from the options given below:

(1)

(4)

(1)

Q 21 : The correct increasing order of C–H (A), C–O (B), C=O (C) and C≡N (D) bonds in terms of covalent bond length is : [2026]

Q 22 : In period 4 of the periodic table, the elements with highest and lowest atomic radii are respectively: [2026]

Q 23 : Consider the following statement: (i) Atomic radii decreases across a row of the periodic table when we move from left to right (ii) Atomic radii increases down the column as we move from top to bottom (iii) Screening effect order s>p>d>f Correct statements are

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Q 6 :

The incorrect decreasing order of atomic radii is [2025]

Q 7 :

The type of oxide formed by the element among Li, Na, Be, Mg, B and Al that has the least atomic radius is : [2025]

Q 8 :

Choose the incorrect trend in the atomic radii (r) of the elements : [2025]

Q 9 :

The correct order of hydration enthalpies is

(A) $K^{+}$ (B) ${Rb}^{+}$ (C) ${Mg}^{2 +}$ (D) ${Cs}^{+}$ (E) ${Ca}^{2 +}$

Choose the correct answer from the options given below: [2023]

Q 10 :

The correct increasing order of the ionic radii is [2023]

Q 11 :

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

(Given: Atomic Number: F : 9, Cl : 17, Na = 11, Mg = 12, Al = 13, K = 19, Ca = 20, Sc = 21) [2023]

Q 12 :

The total number of isoelectronic species from the given set is ________.

$O^{2 -}, F^{-}, Al, {Mg}^{2 +}, {Na}^{+}, O^{+}, Mg, {Al}^{3 +}, F$ [2023]

Q 13 :

The correct orders among the following are: [2025]

A. Atomic radius : B < Al < Ga < In < Tl

B. Electronegativity : Al < Ga < In < Tl < B

C. Density : Tl < In < Ga < Al < B

D. 1st Ionisation Energy : In < Al < Ga < Tl < B

Choose the correct answer from the options given below:

Q 21 :

The correct increasing order of C–H (A), C–O (B), C=O (C) and C≡N (D) bonds in terms of covalent bond length is : [2026]

Q 22 :

In period 4 of the periodic table, the elements with highest and lowest atomic radii are respectively: [2026]

Q 23 :

Consider the following statement:

(i) Atomic radii decreases across a row of the periodic table when we move from left to right

(ii) Atomic radii increases down the column as we move from top to bottom

(iii) Screening effect order $s > p > d > f$

Correct statements are