Which of the following colour changes shown during redox titrations is not correct?

Question

Which of the following colour changes shown during redox titrations is not correct? (A) Cr2O72- oxidises the indicator diphenylamine to produce blue colour showing end point. (B) Iodine formed by oxidation of I- ions gives blue colour with starch showing end point. (C) KMnO4 in the form of MnO4- ions gives pink colour showing end point. (D) Thiosulphate ions (S2O32-) give blue colour showing end point.

Tardigrade Admin · Accepted Answer

Thiosulphate ions do not act as indicator and do not indicate end point by change in colour.

Q. Which of the following colour changes shown during redox titrations is not correct?

$C r_{2} O_{7}^{2 -}$ oxidises the indicator diphenylamine to produce blue colour showing end point.

Iodine formed by oxidation of $I^{-}$ ions gives blue colour with starch showing end point.

$K M n O_{4}$ in the form of $M n O_{4}^{-}$ ions gives pink colour showing end point.

Thiosulphate ions $(S_{2} O_{3}^{2 -})$ give blue colour showing end point.

Thiosulphate ions do not act as indicator and do not indicate end point by change in colour.

Q. Which of the following colour changes shown during redox titrations is not correct?

Cr2​O72−​ oxidises the indicator diphenylamine to produce blue colour showing end point.

Iodine formed by oxidation of I− ions gives blue colour with starch showing end point.

KMnO4​ in the form of MnO4−​ ions gives pink colour showing end point.

Thiosulphate ions (S2​O32−​) give blue colour showing end point.

Thiosulphate ions do not act as indicator and do not indicate end point by change in colour.

$C r_{2} O_{7}^{2 -}$ oxidises the indicator diphenylamine to produce blue colour showing end point.

Iodine formed by oxidation of $I^{-}$ ions gives blue colour with starch showing end point.

$K M n O_{4}$ in the form of $M n O_{4}^{-}$ ions gives pink colour showing end point.

Thiosulphate ions $(S_{2} O_{3}^{2 -})$ give blue colour showing end point.