(C) The correct answer is $(C)$.When $K_2Cr_2O_7$ reacts with an aqueous base like $KOH$,the dichromate ion $(Cr_2O_7^{2-})$ is converted into the chr

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The conversion of dichromate to chromate

(C) The correct answer is $(C)$.When $K_2Cr_2O_7$ reacts with an aqueous base like $KOH$,the dichromate ion $(Cr_2O_7^{2-})$ is converted into the chromate ion $(CrO_4^{2-})$.The chemical reaction is: $K_2Cr_2O_7 + 2KOH \to 2K_2CrO_4 + H_2O$.The $K_2CrO_4$ (potassium chromate) formed is lemon-yellow in colour.

Class 12 Chemistry d-and f-Block Elements Compounds of Transitional elements

Easy

The colour of $K_2Cr_2O_7$ changes from red-orange to lemon-yellow on treatment with aqueous $KOH$ because of:

A
The reduction of $Cr^{VI}$ to $Cr^{III}$
B
The formation of chromium hydroxide
C
The conversion of dichromate to chromate
D
The oxidation of potassium hydroxide to potassium peroxide

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d-and f-Block Elements

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Compounds of Transitional elements

Which one of the following is known as lunar caustic when in fused state?

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The yellow colour of chromates changes to orange on acidification due to the formation of:

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Which one of the following is lunar caustic?

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Fill in the blanks:
$1.$ The copper layer on copper coins in the $UK$ is .......... .
$2.$ Copper-silver coins in the $UK$ are an alloy of ............ .
$3.$ The catalyst used for the oxidation of $SO_2$ to $SO_3$ is ......... .

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Among $CrO$,$Cr_2O_3$,and $CrO_3$,the sum of spin-only magnetic moment values of basic and amphoteric oxides is . . . . . . . . $10^{-2} \ BM$ (nearest integer).
(Given atomic number of $Cr$ is $24$)

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The colour of $K_2Cr_2O_7$ changes from red-orange to lemon-yellow on treatment with aqueous $KOH$ because of:

Similar Questions

Which one of the following is known as lunar caustic when in fused state?

The yellow colour of chromates changes to orange on acidification due to the formation of:

Which one of the following is lunar caustic?

Fill in the blanks:$1.$ The copper layer on copper coins in the $UK$ is .......... .$2.$ Copper-silver coins in the $UK$ are an alloy of ............ .$3.$ The catalyst used for the oxidation of $SO_2$ to $SO_3$ is ......... .

Among $CrO$,$Cr_2O_3$,and $CrO_3$,the sum of spin-only magnetic moment values of basic and amphoteric oxides is . . . . . . . . $10^{-2} \ BM$ (nearest integer).(Given atomic number of $Cr$ is $24$)

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Exam Paper Generator

Online Exam Module

Fill in the blanks:
$1.$ The copper layer on copper coins in the $UK$ is .......... .
$2.$ Copper-silver coins in the $UK$ are an alloy of ............ .
$3.$ The catalyst used for the oxidation of $SO_2$ to $SO_3$ is ......... .

Among $CrO$,$Cr_2O_3$,and $CrO_3$,the sum of spin-only magnetic moment values of basic and amphoteric oxides is . . . . . . . . $10^{-2} \ BM$ (nearest integer).
(Given atomic number of $Cr$ is $24$)