Question 1: Palette 1/22

NEET 2026 MCQ

In an acidic medium, 10 mL of 0.25 M oxalic acid is titrated with $\mathrm{KMnO}_4$ solution. If the volume of $\mathrm{KMnO}_4$ solution required to reach end point is 10 mL , the strength of the $\mathrm{KMnO}_4$ solution is

A

0.15 M

B

0.10 M

C

0.20 M

D

0.25 M

Question 2: Palette 2/22

NEET 2026 MCQ

The correct decreasing order of oxidation state of the $\underline{\mathrm{underlined\, atom}}$ in each molecule is

A

$ \underline{\mathrm{P}}_4 \mathrm{O}_6>\underline{\mathrm{Cl}}_2 \mathrm{O}_7>\underline{\mathrm{A}}\mathrm{l}\mathrm{H}_3 $

B

$ \underline{\mathrm{P}}_4 \mathrm{O}_{10}>\underline{\mathrm{S}}O_3>\mathrm{H}_2 \underline{\mathrm{O}} $

C

$ \underline{\mathrm{N}}_2 \mathrm{O}_5>\underline{\mathrm{Al}}_2 \mathrm{O}_3>\mathrm{H}_2 \underline{\mathrm{~S}} $

D

$ \underline{\mathrm{Pb}}O_2>\underline{\mathrm{N}}_2 \mathrm{O}_3>\underline{\mathrm{S}}O_3 $

Question 3: Palette 3/22

NEET 2025 MCQ

Consider the following compounds :

${\mathrm{\underline{K}O}}_2, \mathrm{H}_2 \underline{\mathrm{O}}_2$ and $\mathrm{H}_2 \underline{S }O_4$

The oxidation state of the underlined elements in them are, respectively,

A

$+1,-2$, and +4

B

$+4,-4$, and +6

C

$+1,-1$, and +6

D

$+2,-2$, and +6

Question 4: Palette 4/22

NEET 2024 MCQ

The oxidation states not shown by Mn in given reaction is :

$ 3 \mathrm{MnO}_4^{2-}+4 \mathrm{H}^{+} \longrightarrow 2 \mathrm{MnO}_4^{-}+\mathrm{MnO}_2+2 \mathrm{H}_2 \mathrm{O} $

A. +6

B. +2

C. +4

D. +7

E. +3

Choose the most appropriate answer from the options given below :

A

D and E only

B

B and D only

C

A and B only

D

B and E only

Question 5: Palette 5/22

NEET 2024 MCQ

Which reaction is NOT a redox reaction?

A

$\mathrm{Zn}+\mathrm{CuSO}_4 \rightarrow \mathrm{ZnSO}_4+\mathrm{Cu}$

B

$2 \mathrm{KClO}_3+\mathrm{I}_2 \rightarrow 2 \mathrm{KIO}_3+\mathrm{Cl}_2$

C

$\mathrm{H}_2+\mathrm{Cl}_2 \rightarrow 2 \mathrm{HCl}$

D

$\mathrm{BaCl}_2+\mathrm{Na}_2 \mathrm{SO}_4 \rightarrow \mathrm{BaSO}_4+2 \mathrm{NaCl}$

Question 6: Palette 6/22

NEET 2023 MCQ

The correct option for a redox couple is:

A

Both are oxidised forms involving same element.

B

Both are reduced forms involving same element.

C

Both the reduced and oxidised forms involve same element.

D

Cathode and anode together.

Question 7: Palette 7/22

NEET 2023 MCQ

On balancing the given redox reaction,

$\mathrm{aCr}_{2} \mathrm{O}_{7}^{2-}+\mathrm{bSO}_{3}^{2-}(\mathrm{aq})+\mathrm{cH}^{+}(\mathrm{aq}) \rightarrow 2 \mathrm{aCr}^{3+}(\mathrm{aq})+\mathrm{bSO}_{4}^{2-}(\mathrm{aq})+\frac{\mathrm{c}}{2} \mathrm{H}_{2} \mathrm{O}(\ell)$

the coefficients $\mathrm{a}, \mathrm{b}$ and $\mathrm{c}$ are found to be, respectively -

A

3, 8, 1

B

1, 8, 3

C

8, 1, 3

D

1, 3, 8

Question 8: Palette 8/22

NEET 2022 MCQ

Which of the following reactions is a decomposition redox reaction?

A

P₄(s) + 3OH^$-$(aq) + 3H₂O(l) $\to$ PH₃(g) + 3H₂PO$_2^ - $(aq)

B

2Pb(NO₃)₂(s) $\to$ 2PbO(s) + 4NO₂(g) + O₂(g)

C

N₂(g) + O₂(g) $\to$ 2NO(g)

D

Cl₂(g) + 2OH^$-$(aq) $\to$ ClO^$-$(aq) + Cl^$-$(aq) + 4H₂O(l)

Question 9: Palette 9/22

NEET 2020 MCQ

What is the change in oxidation number of carbon in the following reaction?
CH₄(g) + 4Cl₂(g) $ \to $ CCl₄(l) + 4HCl(g)

A

0 to + 4

B

$ - $4 to + 4

C

0 to $ - $ 4

D

+ 4 to + 4

Question 10: Palette 10/22

NEET 2019 MCQ

Which of the following reactions are disproportionation reaction?

(a) 2Cu⁺ $ \to $ Cu²⁺ + Cu⁰
(b) 3MnO₄^2- + 4H⁺ $ \to $ 2MnO₄^- + MnO₂ + 2H₂O
(c) 2KMnO₄ $\buildrel \Delta \over \longrightarrow $ K₂MnO₄ + MnO₂ + O₂
(d) 2MnO₄^- + 3Mn²⁺ + 2H₂O $ \to $ 5MnO₂ + 4${H^ \oplus }$

Select the correct option from the following :

A

(a), (c) and (d)

B

(a) and (b) only

C

(a) and (d) only

D

(a), (b) and (c)

Question 11: Palette 11/22

NEET 2018 MCQ

The correct order of N-compounds in its decreasing order of oxidation states is

A

HNO₃ , NO, N₂ , NH₄Cl

B

HNO₃ , NO, NH₄Cl, N₂

C

HNO₃ , NH₄Cl, NO, N

D

NH₄Cl, N₂ , NO, HNO₃

Question 12: Palette 12/22

NEET 2018 MCQ

For the redox reaction,
MnO₄^– + C₂O₄ ^2– + H⁺ $ \to $ Mn²⁺ + CO₂ + H₂O
The correct coefficients of the reactants for the balanced equation are

A

MnO4-	C2O42-	H+
16	5	2

B

MnO4-	C2O42-	H+
2	5	16

C

MnO4-	C2O42-	H+
2	16	5

D

MnO4-	C2O42-	H+
5	16	2

Question 13: Palette 13/22

NEET 2016 MCQ

Hot concentrated sulphate acid is a moderately strong oxidizing agent. Which of the following reactions does not show oxidizing behaviour?

A

Cu + 2H₂SO₄ $ \to $ CuSO₄ + SO₂ + 2H₂O

B

S + 2H₂SO₄ $ \to $ 3SO₂ + 2H₂O

C

C + 2H₂SO₄ $ \to $ CO₂ + 2SO₂ + 2H₂O

D

CaF₂ + H₂SO₄ $ \to $ CaSO₄ + 2HF

Question 14: Palette 14/22

NEET 2014 MCQ

(I)   H₂O₂ + O₃ $ \to $ H₂O + 2O₂
(II)   H₂O₂ + Ag₂O $ \to $ 2Ag + H₂O + O₂
Role of Hydrogen peroxide in the above reactions is respectvely

A

oxidizing in (I) and reducing in (II)

B

reducing in (I) and oxidizing (II)

C

reducing in (I) and (II)

D

oxidizing in (I) and (II)

Question 15: Palette 15/22

NEET 2014 MCQ

In acidic medium, H₂O₂ changes Cr₂O₇^2- to CrO₅ which has two

($-$O$-$O$-$) bonds. Oxidation state of Cr in CrO₅ is

A

+5

B

+3

C

+6

D

$-$10

Question 16: Palette 16/22

NEET 2014 MCQ

The pair of compounds that can exist together is

A

FeCl₃, SnCl₂

B

HgCl₂, SnCl₂

C

FeCl₂, SnCl₂

D

FeCl₃, KI

Question 17: Palette 17/22

NEET 2012 MCQ

When Cl₂ gas reacts with hot and concentrated sodium hydroxide solution, the oxidation number of chlorine changes from

A

zero to +1 and zero to $-$5

B

zero to $-$1 and zero to +5

C

zero to $-$1 and zero to +3

D

zero to +1 and zero to $-$3

Question 18: Palette 18/22

NEET 2012 MCQ

A mixture of potassium chlorate, oxalic acid and sulphuric acid is heated. During the reaction which element undergoes maximum change in the oxidation number?

A

S

B

H

C

Cl

D

C

Question 19: Palette 19/22

NEET 2009 MCQ

Oxidation numbers of P in PO$_4^{3 - }$, of S in SO$_4^{2 - }$ and that of Cr in Cr₂O$_7^{2 - }$ are respectively

A

+3, +6 and +5

B

+5, +3 and +6

C

$-$3, +6 and + 6

D

+5, +6 and +6

Question 20: Palette 20/22

NEET 2008 MCQ

Number of moles of MnO$_4^{ - }$ required to oxidize one mole of ferrous oxalate completely in acidic medium will be

A

7.5 moles

B

0.2 moles

C

0.6 moles

D

0.4 moles

Question 21: Palette 21/22

NEET 2004 MCQ

Which is the best description of the behaviour of bromine in the reaction given below?
H₂O + Br₂ $ \to $ HOBr + HBr

A

Proton acceptor only

B

Both oxidised and reduced

C

Oxidised only

D

Reduced only

Question 22: Palette 22/22

NEET 2003 MCQ

The oxidation states of sulphur in the anions

SO3${_3^{2 - }}$, S₂O${_4^{2 - }}$ and S₂O${_6^{2 - }}$ follow the order

A

S₂O${_4^{2 - }}$ < SO${_3^{2 - }}$ < S₂O${_6^{2 - }}$

B

SO${_3^{2 - }}$ < S₂O${_4^{2 - }}$ < S₂O${_6^{2 - }}$

C

S₂O${_4^{2 - }}$ < S₂O${_6^{2 - }}$ < SO${_3^{2 - }}$

D

S₂O${_6^{2 - }}$ < S₂O${_4^{2 - }}$ < SO${_3^{2 - }}$