Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A) : An aqueous solution of KOH when for volumetric analysis, its concentration should be checked before the use. Reason (R) : On aging, KOH solution absorbs atmospheric CO 2 . In the light of the above statements, choose the correct answer from the options given below.

Both (A) and (R) are correct and (R) is the correct explanation of (A)

(A) is not correct but (R) is correct

Both (A) and (R) are correct but (R) is not the correct explanation of (A)

(A) is correct but (R) is not correct

Incorrect statement for the use of indicator in acid-base titration is:

Methyl orange may be used for a weak acid vs weak bas titration.

Phenolphthalein may be used for a strong acid vs strong base titration.

Methyl orange is a suitable indicator for a strong acid vs weak base titration.

Phenolphthalein is a suitable indicator for a weak acid vs strong base titration.

When Cu 2 + ion is treated with KI , a white precipitate, X appears in solution. The solution is titrated with sodium thiosulphate, the compound Y is formed. X and Y respectively are

X = Cu 2 I 2 , Y = Na 2 S 4 O 6

X = Cu 2 I 2 , Y = Na 2 S 4 O 5

In which of the following reactions the hydrogen peroxide acts as a reducing agent?

HOCl + H 2 O 2 → H 3 O + + Cl - 1 + O 2

PbS + 4 H 2 O 2 → PbSO 4 + 4 H 2 O

2 Fe 2 + + H 2 O 2 → 2 Fe 3 + + 2 OH -

Mn 2 + + H 2 O 2 → Mn 4 + + 2 OH -

E M B I B E

EMBIBE CHAPTER WISE PREVIOUS YEAR PAPERS FOR CHEMISTRY>Chapter 6 - Redox Reactions>JEE Main - 26 June 2022 Shift 2>Q 47

EASY

JEE Main

IMPORTANT

Earn 100

Which one of the following is an example of disproportionation reaction?

77.78% studentsanswered this correctly

Important Questions on Redox Reactions

EASY

JEE Main

IMPORTANT

EMBIBE CHAPTER WISE PREVIOUS YEAR PAPERS FOR CHEMISTRY>Chapter 6 - Redox Reactions>JEE Main - 27 June 2022 Shift 2>Q 48

In

3 d

series, the metal having the highest

M^{2 +} / M

standard electrode potential is

MEDIUM

JEE Main

IMPORTANT

EMBIBE CHAPTER WISE PREVIOUS YEAR PAPERS FOR CHEMISTRY>Chapter 6 - Redox Reactions>JEE Main - 28 June 2022 Shift 1>Q 49

Dihydrogen reacts with

CuO

to give

HARD

JEE Main

IMPORTANT

EMBIBE CHAPTER WISE PREVIOUS YEAR PAPERS FOR CHEMISTRY>Chapter 6 - Redox Reactions>JEE Main - 28 June 2022 Shift 1>Q 50

A

2.0 g

sample containing

{MnO}_{2}

is treated with

HCl

liberating

{Cl}_{2}

. The

{Cl}_{2}

gas is passed into a solution of

KI

and

60.0 mL

of

0.1 {MNaS}_{2} O_{3}

is required to titrate the liberated iodine. The percentage of

{MnO}_{2}

in the sample is____. Nearest integer)
[Atomic masses (in

u

)

Mn = 55; Cl = 35.5 : O = 16, I = 127, Na = 23, K = 39, S = 32

]

MEDIUM

JEE Main

IMPORTANT

EMBIBE CHAPTER WISE PREVIOUS YEAR PAPERS FOR CHEMISTRY>Chapter 6 - Redox Reactions>JEE Main - 28 June 2022 Shift 2>Q 51

Which of the following oxoacids of sulphur contains "S" in two different oxidation states?

MEDIUM

JEE Main

IMPORTANT

EMBIBE CHAPTER WISE PREVIOUS YEAR PAPERS FOR CHEMISTRY>Chapter 6 - Redox Reactions>JEE Main - 28 June 2022 Shift 2>Q 52

0.01 {MKMnO}_{4}

solution was added to

20.0 mL

of

0.05 M Mohr

's salt solution through a burette. The initial reading of

50 mL

burette is zero. The volume of

{KMnO}_{4}

solution left in the burette after the end point is.......

mL

. (nearest integer)

HARD

JEE Main

IMPORTANT

EMBIBE CHAPTER WISE PREVIOUS YEAR PAPERS FOR CHEMISTRY>Chapter 6 - Redox Reactions>JEE Main - 25 July 2022 Shift 2>Q 53

In base vs. Acid titration, at the end point methyl orange is present as

MEDIUM

JEE Main

IMPORTANT

EMBIBE CHAPTER WISE PREVIOUS YEAR PAPERS FOR CHEMISTRY>Chapter 6 - Redox Reactions>JEE Main - 26 July 2022 Shift 1>Q 54

Which of the given reactions is not an example of disproportionation reaction?

HARD

JEE Main

IMPORTANT

EMBIBE CHAPTER WISE PREVIOUS YEAR PAPERS FOR CHEMISTRY>Chapter 6 - Redox Reactions>JEE Main - 26 July 2022 Shift 2>Q 55

$20 mL$ of $0.02 M$ hypo solution is used for the titration of $10 mL$ of copper sulphate solution, in the presence of excess of $KI$ using starch as an indicator. The molarity of ${Cu}^{2 +}$ is found to be $_____\times 10^{- 2} M$ (nearest integer)