Question 1: Palette 1/47

NEET 2026 MCQ

The correct order of increasing metallic character of $\mathrm{Na}, \mathrm{Be}, \mathrm{P}, \mathrm{Mg}$ and Si is

A

$\mathrm{P}<\mathrm{Si}<\mathrm{Be}<\mathrm{Mg}<\mathrm{Na}$

B

$\mathrm{P}<\mathrm{Si}<\mathrm{Na}<\mathrm{Mg}<\mathrm{Be}$

C

$\mathrm{P}<\mathrm{Mg}<\mathrm{Be}<\mathrm{Si}<\mathrm{Na}$

D

$\mathrm{Be}<\mathrm{Si}<\mathrm{P}<\mathrm{Mg}<\mathrm{Na}$

Question 2: Palette 2/47

NEET 2026 MCQ

Identify the incorrect statement from the following :

A

The largest and the smallest species among $\mathrm{Mg}, \mathrm{Mg}^{2+}, \mathrm{Al}$ and $\mathrm{Al}^{3+}$ are Al and $\mathrm{Mg}^{2+}$ respectively.

B

The IUPAC name of the element with atomic number 107 is Unnilseptium.

C

The similarity in behaviour of Li with Mg is referred to as 'diagonal relationship'

D

The oxidation state and covalency of Al in $\left[\mathrm{AlCl}\left(\mathrm{H}_2 \mathrm{O}\right)_5\right]^{2+}$ are 3 and 6, respectively.

Question 3: Palette 3/47

NEET 2026 MCQ

Among the following options, the correct trend in the electron gain enthalpy is

A

$\mathrm{I}>\mathrm{Br}>\mathrm{Cl}>\mathrm{F}$

B

$\mathrm{F}>\mathrm{Cl}>\mathrm{Br}>\mathrm{I}$

C

$\mathrm{Br}>\mathrm{Cl}>\mathrm{F}>\mathrm{I}$

D

$\mathrm{Cl}>\mathrm{F}>\mathrm{Br}>\mathrm{I}$

Question 4: Palette 4/47

NEET 2026 MCQ

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 O is lower than that of N and F .

Reason R: The loss of an electron from O leads to stable half-filled $p$ orbital

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

A

$\mathbf{A}$ is not correct but $\mathbf{R}$ is correct

B

Both $\mathbf{A}$ and $\mathbf{R}$ are correct and $\mathbf{R}$ is the correct explanation of $\mathbf{A}$

C

Both $\mathbf{A}$ and $\mathbf{R}$ are correct and $\mathbf{R}$ is NOT the correct explanation of $\mathbf{A}$

D

$\mathbf{A}$ is correct but $\mathbf{R}$ is not correct.

Question 5: Palette 5/47

NEET 2025 MCQ

Which of the following statements are true?

A. Unlike Ga that has a very high melting point, Cs has a very low melting point.

B. On Pauling scale, the electronegativity values of N and Cl are not the same.

C. $\mathrm{Ar}, \mathrm{K}^{+}, \mathrm{Cl}^{-}, \mathrm{Ca}^{2+}$, and $\mathrm{S}^{2-}$ are all isoelectronic species.

D. The correct order of the first ionization enthalpies of $\mathrm{Na}, \mathrm{Mg}, \mathrm{Al}$, and Si is $\mathrm{Si}>\mathrm{Al}>\mathrm{Mg}>\mathrm{Na}$.

E. The atomic radius of Cs is greater than that of Li and Rb.

Choose the correct answer from the options given below :

A

C and D only

B

A, C, and E only

C

A, B, and E only

D

C and E only

Question 6: Palette 6/47

NEET 2025 MCQ

Which among the following electronic configurations belong to main group elements?

A. $[\mathrm{Ne}] 3 \mathrm{~s}^1$

B. $[\operatorname{Ar}] 3 \mathrm{~d}^3 4 \mathrm{~s}^2$

C. $[K r] 4 d^{10} 5 s^2 5 p^5$

D. $[\operatorname{Ar}] 3 \mathrm{~d}^{10} 4 \mathrm{~s}^1$

E. $[R n] 5 f^0 6 d^2 7 s^2$

Choose the correct answer from the option given below :

A

D and E only

B

A, C and D only

C

B and E only

D

A and C only

Question 7: Palette 7/47

NEET 2024 MCQ

The correct decreasing order of atomic radii (pm) of $\mathrm{Li}, \mathrm{Be}, \mathrm{B}$ and $\mathrm{C}$ is

A

$\mathrm{Be}>\mathrm{Li}>\mathrm{B}>\mathrm{C}$

B

$\mathrm{Li}>\mathrm{Be}>\mathrm{B}>\mathrm{C}$

C

$\mathrm{C}>\mathrm{B}>\mathrm{Be}>\mathrm{Li}$

D

$\mathrm{Li}>\mathrm{C}>\mathrm{Be}>\mathrm{B}$

Question 8: Palette 8/47

NEET 2024 MCQ

Match List I with List II :

	List - I (Atom/Molecule)		List - II (Property)
(A)	Nitrogen atom	(I)	Paramagnetic
(B)	Fluorine molecule	(II)	Most relative element in group 18
(C)	Oxygen molecule	(III)	Element with highest ionisation enthalpy in group 15
(D)	Xenon atom	(IV)	Strongest oxidising agent

Identify the correct answer from the options given below :

A

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

B

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

C

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

D

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

Question 9: Palette 9/47

NEET 2024 MCQ

Arrange the following elements in increasing order of first ionization enthalpy: $\mathrm{Li}, \mathrm{Be}, \mathrm{B}, \mathrm{C}, \mathrm{N}$

Choose the correct answer from the options given below:

A

$ \mathrm{Li}<\mathrm{Be}<\mathrm{B}<\mathrm{C}<\mathrm{N} $

B

$ \mathrm{Li}<\mathrm{B}<\mathrm{Be}<\mathrm{C}<\mathrm{N} $

C

$ \mathrm{Li}<\mathrm{Be}<\mathrm{C}<\mathrm{B}<\mathrm{N} $

D

$ \mathrm{Li}<\mathrm{Be}<\mathrm{N}<\mathrm{B}<\mathrm{C} $

Question 10: Palette 10/47

NEET 2024 MCQ

Arrange the following elements in increasing order of electronegativity:

N, O, F, C, Si

Choose the correct answer from the options given below :

A

Si < C < N < O < F

B

Si < C < O < N < F

C

O < F < N < C < Si

D

F < O < N < C < Si

Question 11: Palette 11/47

NEET 2023 MCQ

Which of the following is correctly matched?

A

Basic oxides $\Rightarrow \mathrm{In}_2 \mathrm{O}_3, \mathrm{~K}_2 \mathrm{O}, \mathrm{SnO}_2$

B

Neutral oxides $\Rightarrow \mathrm{CO}, \mathrm{NO}_2, \mathrm{~N}_2 \mathrm{O}$

C

Acidic oxides $\Rightarrow \mathrm{Mn}_2 \mathrm{O}_7, \mathrm{SO}_2, \mathrm{TeO}_3$

D

Amphoteric oxides $\Rightarrow \mathrm{BeO}, \mathrm{Ga}_2 \mathrm{O}_3, \mathrm{GeO}$

Question 12: Palette 12/47

NEET 2023 MCQ

The correct sequence given below containing neutral, acidic, basic and amphoteric oxide each, respectively, is

A

NO, ZnO, CO$_2$, CaO

B

ZnO, NO, CaO, CO$_2$

C

NO, CO$_2$, ZnO, CaO

D

NO, CO$_2$, CaO, ZnO

Question 13: Palette 13/47

NEET 2022 MCQ

The correct order of first ionization enthalpy for the given four elements is :

A

C < F < N < O

B

C < N < F < O

C

C < N < O < F

D

C < O < N < F

Question 14: Palette 14/47

NEET 2022 MCQ

Decrease in size from left to right in actinoid series is greater and gradual than that in lanthanoid series due to

A

5f orbitals have greater shielding effect

B

4f orbitals are penultimate

C

4f orbitals have greater shielding effect

D

5f orbitals have poor shielding effect

Question 15: Palette 15/47

NEET 2022 MCQ

Fluorine is a stronger oxidising agent than chlorine because :

(a) F-F bond has a low enthalpy of dissociation.

(b) Fluoride ion (F^$-$) has high hydration enthalpy.

(c) Electron gain enthalpy of fluorine is less negative than chlorine.

(d) Fluorine has a very small size.

Choose the most appropriate answer from the options given :

A

(b) and (c) only

B

(a) and (b) only

C

(a) and (c) only

D

(a) and (d) only

Question 16: Palette 16/47

NEET 2022 MCQ

If first ionization enthalpies of elements X and Y are 419 kJ mol^$-$1 and 590 kJ mol^$-$1, respectively and second ionization enthalpies of X and Y are 3069 kJ mol^$-$1 and 1145 kJ mol^$-$1, respectively. Then correct statement is :

A

Both X and Y are alkaline earth metals

B

X is an alkali metal and Y is an alkaline earth metal

C

X is an alkaline earth metal and Y is an alkali metal

D

Both X and Y are alkali metals

Question 17: Palette 17/47

NEET 2022 MCQ

The IUPAC name of an element with atomic number 119 is

A

ununennium

B

unnilennium

C

unununnium

D

ununoctium

Question 18: Palette 18/47

NEET 2022 MCQ

Gadolinium has a low value of third ionisation enthalpy because of

A

small size

B

high exchange enthalpy

C

high electronegativity

D

high basic character

Question 19: Palette 19/47

NEET 2020 MCQ

Identify the incorrect match.

Name			IUPAC Official Name
(A)	Unnilunium	(i)	Mendelevium
(B)	Unniltrium	(ii)	Lawrencium
(C)	Unnilhexium	(iii)	Seaborgium
(D)	Unununnium	(iv)	Darmstadtium

A

(B), (ii)

B

(C), (iii)

C

(D), (iv)

D

(A), (i)

Question 20: Palette 20/47

NEET 2020 MCQ

Match the following :

Oxide			Nature
(A)	CO	(i)	Basic
(B)	BaO	(ii)	Neutral
(C)	Al2O3	(iii)	Acidic
(D)	Cl2O7	(iv)	Amphoteric

Which of the following is correct option?

A

(A)	(B)	(C)	(D)
(ii)	(i)	(iv)	(iii)

B

(A)	(B)	(C)	(D)
(iii)	(iv)	(i)	(ii)

C

(A)	(B)	(C)	(D)
(iv)	(iii)	(ii)	(i)

D

(A)	(B)	(C)	(D)
(i)	(ii)	(iii)	(iv)

Question 21: Palette 21/47

NEET 2019 MCQ

For the second period elements the correct increasing order of first ionization enthalpy is :

A

Li < B < Be < C < N < O < F < Ne

B

Li < Be < B < C < O < N < F < Ne

C

Li < B < Be < C < O < N < F < Ne

D

Li < Be < B < C < N < O < F < Ne

Question 22: Palette 22/47

NEET 2018 MCQ

The correct order of atomic radii in group 13 elements is

A

B < Al < In < Ga < Tl

B

B < Al < Ga < In < Tl

C

B < Ga < Al < Tl < In

D

B < Ga < Al < In < Tl

Question 23: Palette 23/47

NEET 2018 MCQ

Which of the following oxides is most acidic in nature?

A

MgO

B

BeO

C

BaO

D

CaO

Question 24: Palette 24/47

NEET 2017 MCQ

The element Z = 114 has been discovered recently. It will belong to which of the following family/group and electronic configuration ?

A

Carbon family, [Rn] 5f¹⁴ 6d¹⁰ 7s² 7p²

B

Oxygen family, [Rn] 5f¹⁴ 6d¹⁰ 7s² 7p⁴

C

Nitrogen family, [Rn] 5f¹⁴ 6d¹⁰ 7s² 7p⁶

D

Halogen family, [Rn] 5f¹⁴ 6d¹⁰ 7s² 7p⁵

Question 25: Palette 25/47

NEET 2016 MSQ

In which of the following options the order of arrangement does not agree with the variation of property indicated against it ?

A

I < Br < Cl < F (increasing electron gain enthalpy)

B

Li < Na < K < Rb (increasing metallic radius)

C

Al³⁺ < Mg²⁺ < Na⁺ < F^$-$ (increasing ionic size)

D

B < C < N < O (increasing first ionisation enthalpy)

Question 26: Palette 26/47

NEET 2015 MCQ

The species Ar, K⁺ and Ca²⁺ contain the same number of electrons. In which order do their radii increase ?

A

Ca²⁺ < K⁺ < Ar

B

K⁺ < Ar < Ca²⁺

C

Ar < K⁺ < Ca²⁺

D

Ca²⁺ < Ar < K⁺

Question 27: Palette 27/47

NEET 2014 MCQ

Which of the following orders of ionic radii is correctly represented ?

A

H^$-$ > H$^ \bullet $ > H⁺

B

Na⁺ > F^$-$ > O^2$-$

C

F^$-$ > O^2$-$ > Na⁺

D

A$l$³⁺ > Mg²⁺ > N^3$-$

Question 28: Palette 28/47

NEET 2013 MCQ

Which one of the following arrangements represents the correct order of least negative to most negative electron gain enthalpy for C, Ca, Al, F and O?

A

A$l$ < Ca < O < C < F

B

A$l$ < O < C < Ca < F

C

C < F < O < A$l$ < Ca

D

Ca < A$l$ < C < O < F

Question 29: Palette 29/47

NEET 2012 MCQ

Identify the wrong statement in the following.

A

Amongst isoelectronic species, smaller the positive charge on the cation, smaller is the ionic radius.

B

Amongst isoelectronic species, greater the negative charge on the anion, larger is the ionic radius.

C

Atomic radius of the elements increases as one moves down the first group of the periodic table.

D

Atomic radius of the elements decreases as one moves across from left to right in the 2^nd period of the periodic table.

Question 30: Palette 30/47

NEET 2011 MCQ

What is the value of electron gain enthalpy of Na⁺ if IE₁ of Na = 5.1 eV?

A

$-$ 5.1 eV

B

$-$ 10.2 eV

C

+2.55 eV

D

+10.2 eV

Question 31: Palette 31/47

NEET 2010 MCQ

Among the elements Ca, Mg, P and Cl, the order of increasing atomic radii is

A

Mg < Ca < Cl < P

B

Cl < P < Mg < Ca

C

P < Cl < Ca < Mg

D

Ca < Mg < P < Cl

Question 32: Palette 32/47

NEET 2010 MCQ

Among the following which one has the highest cation to anion size ratio ?

A

CsI

B

CsF

C

LiF

D

NaF

Question 33: Palette 33/47

NEET 2010 MCQ

The correct order of the decreasing ionic radii among the following isoelectronic species is

A

Ca²⁺ > K⁺ > S^2$-$ > C$l$^$-$

B

C$l$^$-$ > S^2$-$ > Ca²⁺ > K⁺

C

S^2$-$ > Cl^$-$ > K⁺ > Ca²⁺

D

K⁺ > Ca²⁺ > Cl^$-$ > S^2$-$

Question 34: Palette 34/47

NEET 2010 MCQ

Which of the following represents the correct order of increasing electron gain enthalpy with negative sign for the elements O, S, F and C$l$ ?

A

C$l$ < F < O < S

B

O < S < F < C$l$

C

F < S < O < C$l$

D

S < O < C$l$ < F

Question 35: Palette 35/47

NEET 2009 MCQ

Amongst the elements with following electronic configurations, which one of them may have the highest ionisation energy ?

A

Ne [3s² 3p²]

B

Ar [3d¹⁰ 4s² 4p³]

C

Ne [3s² 3p¹]

D

Ne [3s² 3p³]

Question 36: Palette 36/47

NEET 2008 MSQ

Which one of the following arrangements does not give the correct picture of the trends indicated against it ?

A

F₂ > Cl₂ > Br₂ > I₂ : Bond dissociation energy

B

F₂ > Cl₂ > Br₂ > I₂ : Electronegativity

C

F₂ > Cl₂ > Br₂ > I₂ : Oxidizing power

D

F₂ > Cl₂ > Br₂ > I₂ : Electron gain enthalpy

Question 37: Palette 37/47

NEET 2007 MCQ

Identify the correct order of the size of the following :

A

Ca²⁺ < K⁺ < Ar < Cl^$-$ < S^2$-$

B

Ar < Ca²⁺ < K⁺ < Cl^$-$ < S^2$-$

C

Ca²⁺ < Ar < K⁺ < Cl^$-$ < S^2$-$

D

Ca²⁺ < K⁺ < Ar < S^2$-$ < Cl^$-$

Question 38: Palette 38/47

NEET 2007 MCQ

Which one of the following ionic species has the greatest proton affinity to form stable compound ?

A

NH$_2^ - $

B

F^$-$

C

I^$-$

D

HS^$-$

Question 39: Palette 39/47

NEET 2007 MCQ

With which of the following electronic configuration an atom has the lowest ionisation enthalpy ?

A

1s² 2s² 2p³

B

1s² 2s² 2p⁵ 3s¹

C

1s² 2s² 2p⁶

D

1s² 2s² 2p⁵

Question 40: Palette 40/47

NEET 2006 MCQ

Which one of the following orders is not in accordance with the property stated against it?

A

F₂ > Cl₂ > Br₂ > I₂ : Bond dissociation energy

B

F₂ > Cl₂ > Br₂ > I₂ : Oxidising power

C

HI > HBr > HCl > HF : Acidic property in water

D

F₂ > Cl₂ > Br₂ > I₂ : Electronegativity.

Question 41: Palette 41/47

NEET 2006 MCQ

Which one of the following orders is not in accordance with the property stated against it ?

A

F₂ > Cl₂ > Br₂ > I₂ : Bond dissociation energy

B

F₂ > Cl₂ > Br₂ > I₂ : Oxidising power

C

HI > HBr > HCl > HF : Acidic property in water

D

F₂ > Cl₂ > Br₂ > I₂ : Electronegativity

Question 42: Palette 42/47

NEET 2005 MCQ

Which one of the following arrangements represents the correct order of electron gain enthalpy (with negative sign) of the given atomic species ?

A

S < O < Cl < F

B

Cl < F < S < O

C

F < Cl < O < S

D

O < S < F < Cl

Question 43: Palette 43/47

NEET 2004 MCQ

Ionic radii are

A

inversely proportional to effective nuclear charge

B

inversely proportional to square of effective nuclear charge

C

directly proportional to effective nuclear charge

D

directly proportional to square of effective nuclear charge.

Question 44: Palette 44/47

NEET 2003 MCQ

The ions O^2$-$, F^$-$, Na⁺, Mg²⁺ and Al³⁺ are isoelectronic. Their ionic radii show

A

a significant increase from O^2$-$ to Al³⁺

B

a significant decrease from O^2$-$ to Al³⁺

C

an increase from O2^$-$ to F^$-$ and then decrease from Na⁺ to Al³⁺

D

a decrease from O2^$-$ to F^$-$ and then increase from Na⁺ to Al³⁺.

Question 45: Palette 45/47

NEET 2002 MCQ

Which of the following order is wrong?

A

NH₃ < PH₃ < AsH₃ $-$ acidic

B

Li < Be < B < C $-$ 1^st IP

C

Al₂O₃ < MgO < Na₂O < K₂O $-$ basic

D

Li⁺ < Na⁺ < K⁺ < Cs⁺ $-$ ionic radius.

Question 46: Palette 46/47

NEET 2001 MCQ

Correct order of 1^st ionization potential among following elements Be, B, C, N, O is

A

B < Be < C < O < N

B

B < Be < C < N < O

C

Be < B < C < N < O

D

Be < B < C < O < N

Question 47: Palette 47/47

NEET 2000 MCQ

Which statement is wrong ?

A

Bond energy of F₂ > Cl₂

B

Electronegativity of F > Cl

C

F is more oxidising than Cl

D

Electron affinity of Cl > F