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Which of the following options are correct for the reaction \( 2[\mathrm{Au}(\mathrm{CN})_2]^{-} \, (\mathrm{aq.}) + \mathrm{Zn}(s) \rightarrow 2\mathrm{Au}(s) + [\mathrm{Zn}(\mathrm{CN})_4]^{2-} (\mathrm{aq}) \)?

Potassium dichromate acts as a strong oxidizing agent in acidic solution. During this process, the oxidation state changes from

\( 2\mathrm{IO}_3^- + x\,\mathrm{I}^- + 12\mathrm{H}^+ \rightarrow 6\mathrm{I}_2 + 6\mathrm{H}_2\mathrm{O} \). What is the value of \( x \)?

The covalency and oxidation state respectively of boron in \( \mathrm{[BF_4]^{-}} \), are:

The sum of oxidation state of the metals in \( \mathrm{Fe(CO)_5} \), \( \mathrm{VO^{2+}} \) and \( \mathrm{WO_3} \) is __________.

Given below are two statements:
Statement I: In redox titration, the indicators used are sensitive to change in pH of the solutions
Statement II: In acid – base titration, the indicators used are sensitive to change in oxidation potential.
In the light of the above statements, choose the most appropriate answer from the Option given below

\( \mathrm{H_2O_2} \) acts as a reducing agent in.

‘\( 25 \) volume’ hydrogen peroxide means

See the following chemical reaction:
\( \mathrm{Cr_2O_7^{2-}} + X\mathrm{H^+} + 6\mathrm{F_e^{2+}} \rightarrow Y\mathrm{Cr^{3+}} + 6\mathrm{F_e^{3+}} + Z\mathrm{H_2O} \)
The sum of \( X \), \( Y \) and \( Z \) is __________.

In Chromyl chloride, the oxidation state of chromium is (+) __________.

The number of electrons involved in the reduction permanganate to manganese dioxide in acidic medium is _______.

The standard electrode potential \( (\mathrm{M^{3+}} / \mathrm{M^{2+}}) \) for \( \mathrm{V} \), \( \mathrm{Cr} \), \( \mathrm{Mn} \) and \( \mathrm{Co} \) are \( -0.26 \ \mathrm{V} \), \( -0.41 \ \mathrm{V} \), \( +1.57 \ \mathrm{V} \) and \( +1.97 \ \mathrm{V} \), respectively. The metal ions which can liberate \( \mathrm{H_2} \) from a dilute acid are;

\( \mathrm{KMnO_4} \) is titrated with ferrous ammonium sulphate hexahydrate in presence of dilute \( \mathrm{H_2SO_4} \). Number of water molecules produced for \( 2 \) molecules of \( \mathrm{KMnO_4} \) is _______.

During the reaction of permanganate with thiosulphate, the change in oxidation of manganese occurs by value of \( 3 \). Identify which of the below medium will favour the reaction.

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JEE Main 2023 25th Jan Morning Shift

‘\( 25 \) volume’ hydrogen peroxide means