Redox Reactions · Chemistry · NEET

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MCQ (Single Correct Answer)

1

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

RE-NEET 2026
2

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

RE-NEET 2026
3

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,

NEET 2025
4

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 :

NEET 2024 (Re-Examination)
5

Which reaction is NOT a redox reaction?

NEET 2024
6

The correct option for a redox couple is:

NEET 2023 Manipur
7

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 -

NEET 2023
8

Which of the following reactions is a decomposition redox reaction?

NEET 2022 Phase 2
9
What is the change in oxidation number of carbon in the following reaction?
CH4(g) + 4Cl2(g) $$ \to $$ CCl4(l) + 4HCl(g)
NEET 2020 Phase 1
10
Which of the following reactions are disproportionation reaction?

(a) 2Cu+ $$ \to $$ Cu2+ + Cu0
(b) 3MnO42- + 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 :
NEET 2019
11
The correct order of N-compounds in its decreasing order of oxidation states is
NEET 2018
12
For the redox reaction,
MnO4 + C2O4 2– + H+ $$ \to $$ Mn2+ + CO2 + H2O
The correct coefficients of the reactants for the balanced equation are
NEET 2018
13
Hot concentrated sulphate acid is a moderately strong oxidizing agent. Which of the following reactions does not show oxidizing behaviour?
NEET 2016 Phase 2
14
(I)   H2O2 + O3 $$ \to $$ H2O + 2O2
(II)   H2O2 + Ag2O $$ \to $$ 2Ag + H2O + O2
Role of Hydrogen peroxide in the above reactions is respectvely
AIPMT 2014
15
In acidic medium, H2O2 changes Cr2O72- to CrO5 which has two

($$-$$O$$-$$O$$-$$) bonds. Oxidation state of Cr in CrO5 is
AIPMT 2014
16
The pair of compounds that can exist together is
AIPMT 2014
17
When Cl2 gas reacts with hot and concentrated sodium hydroxide solution, the oxidation number of chlorine changes from
AIPMT 2012 Prelims
18
A mixture of potassium chlorate, oxalic acid and sulphuric acid is heated. During the reaction which element undergoes maximum change in the oxidation number?
AIPMT 2012 Prelims
19
Oxidation numbers of P in PO$$_4^{3 - }$$, of S in SO$$_4^{2 - }$$ and that of Cr in Cr2O$$_7^{2 - }$$ are respectively
AIPMT 2009
20
Number of moles of MnO$$_4^{ - }$$ required to oxidize one mole of ferrous oxalate completely in acidic medium will be
AIPMT 2008
21
Which is the best description of the behaviour of bromine in the reaction given below?
H2O + Br2 $$ \to $$ HOBr + HBr
AIPMT 2004
22
The oxidation states of sulphur in the anions

SO3$${_3^{2 - }}$$, S2O$${_4^{2 - }}$$ and S2O$${_6^{2 - }}$$ follow the order
AIPMT 2003