Some Important Compounds of Transition Metals

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Some Important Compounds of Transition Metals: Overview

This topic covers concepts, such as Important Compounds of d-Block Elements, Potassium Dichromate, Preparation of Potassium Dichromate, pH Dependent Equilibrium between Dichromate and Chromate Ions, and Structures of Dichromate and Chromate Ions.

Important Questions on Some Important Compounds of Transition Metals

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Chemistry>The d- and f-Block Elements>Some Important Compounds of Transition Metals> Q 1

A compound which is a strong oxidizing agent and has orange coloured crystal. It is used in the preparation of azo compounds. Identify the compound:

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Chemistry>The d- and f-Block Elements>Some Important Compounds of Transition Metals> Q 2

On oxidation of S2O32− by MnO4−  in neutral aqueous medium, the oxidation number of S would change from:

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Chemistry>The d- and f-Block Elements>Some Important Compounds of Transition Metals> Q 3

On complete oxidation of   Fe 2+  by  Cr 2 O 7 2−  in acidic medium, the oxidation state of Cr will change from:

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Chemistry>The d- and f-Block Elements>Some Important Compounds of Transition Metals> Q 4

The solution of potassium dichromate is prepared from which of the following compound and how its colour changes with change in pH:

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Chemistry>The d- and f-Block Elements>Some Important Compounds of Transition Metals> Q 5

The number of moles of KMnO4 that will be needed to react with one mole of sulphite ion in acidic solution is:

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Chemistry>The d- and f-Block Elements>Some Important Compounds of Transition Metals> Q 6

Which of the following reaction is spontaneous oxidation-reduction reaction?

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Chemistry>The d- and f-Block Elements>Some Important Compounds of Transition Metals> Q 7

KMnO4 on heating to red hot gives

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Chemistry>The d- and f-Block Elements>Some Important Compounds of Transition Metals> Q 8

In KMnO4, oxidation number of Mn is

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Chemistry>The d- and f-Block Elements>Some Important Compounds of Transition Metals> Q 9

In the reaction: NaCl+K2Cr2O7+H2SO4Conc.→heatX+Na2SO4+K2SO4+H2O, X is a reddish brown gas which gives a yellow solution on passing through water and a yellow precipitate on treating the solution with lead acetate solution. X could be

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Chemistry>The d- and f-Block Elements>Some Important Compounds of Transition Metals> Q 10

When K2Cr2O7 crystals are heated with conc. HCl, the gas evolved is

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Chemistry>The d- and f-Block Elements>Some Important Compounds of Transition Metals> Q 11

In the dichromate ion

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Chemistry>The d- and f-Block Elements>Some Important Compounds of Transition Metals> Q 12

When a manganous salt is treated with KMnO4​ in alkaline medium, the oxidation number if Mn changes from +2 to:

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Chemistry>The d- and f-Block Elements>Some Important Compounds of Transition Metals> Q 13

When thiosulphate ion is oxidised by iodine, which one of the following ion is produced?
 

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Chemistry>The d- and f-Block Elements>Some Important Compounds of Transition Metals> Q 14

What is the melting point of potassium dichromate?

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Chemistry>The d- and f-Block Elements>Some Important Compounds of Transition Metals> Q 15

Which of the following statements is/are false?

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Chemistry>The d- and f-Block Elements>Some Important Compounds of Transition Metals> Q 16

A solution of KMnO4 is reduced to various products depending upon its pH.

I. At pH<7, it is reduced to a colourless solution (A).

II. At pH=7, it forms a brown precipitate (B).

III. At pH>7, it gives a green solution (C).

Then A, B and C, respectively are

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Chemistry>The d- and f-Block Elements>Some Important Compounds of Transition Metals> Q 17

Which of the following sodium salts, on heating with solid  K2Cr2O7  and concentrated H2SO4, gives red vapour?

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Chemistry>The d- and f-Block Elements>Some Important Compounds of Transition Metals> Q 18

Which of the following species has oxygen in -1 oxidation state?

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Chemistry>The d- and f-Block Elements>Some Important Compounds of Transition Metals> Q 19

How many peroxy linkages are present in CrO5 ?

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Chemistry>The d- and f-Block Elements>Some Important Compounds of Transition Metals> Q 20

Treatment of alkaline KMnO4 solution with KI solution oxidizes iodide to:-