D and F - Block...

Which is most basic oxide of chromium?

The basic character of the transition metal monoxides follows the order

(Atomic Number, Ti = 22, V = 23, Cr = 24, Fe = 26)

MnO₄^-  + S^2- + H⁺ → Mn²⁺ +S + H₂O When this equation is balanced, the total number of coefficients on the left hand side are

when this equation is balanced, the num ber of OF^- ions added

One mole of each KMnO₄ and K₂Cr₂O₇ can oxidise ........... moles of ferrous ion.

is of intense pink colour, though Mn is in (+7) oxidation state. It is due to

Which of the following is incorrect statement?

Pyrolusite in MnO₂ is used to prepare KMnO₄. Steps are

Here, I and II are

Which is the correct statem ent about  structure?

Out of Cr (VI) as  , which is better oxidising agent?

The number of moles of acidified KMnO4 required to convert one mole of sulphite ion into sulphate ion is-

CrO₃ dissolves in aqueous NaOH to give-

Solution of MnO₄- is purple-coloured due to-

Which of the following statements is not true?

Transition elements having more tendency to form complex than representative elements (s and p-block elements) due to-

Comprehension Type

Direction (Q. Nos. 16 and 17) This section contains a paragraph, describing theory, experiments, data, etc. Two questions related to the paragraph have been given. Each question has only one correct answer among the four given options (a), (b), (c) and (d).

Passage

Oxides are generally formed by the reaction of metals with oxygen at high temperatures. All the metals except scandium form MO oxides which are ionic. The highest oxidation number in the oxides, coincides with the group number and is attained in Sc₂O₃ to Mn₂O₇. Beyond 7th group, higher oxides coinciding with the group number do not form. As the oxidation number of metal increases covalent character and acidity increases. Mn₂O₇, CrO₃ are acidic and their lower oxides are basic and amphoteric. Stability of higher oxides increases down the group.

Q. 

Which of the following reacts with both acids and bases?

Oxides are generally formed by the reaction of metals with oxygen at high temperatures. All the metals except scandium form MO oxides which are ionic. The highest oxidation number in the oxides, coincides with the group number and is attained in Sc₂O₃ to Mn₂O₇. Beyond 7th group, higher oxides coinciding with the group number do not form. As the oxidation number of metal increases covalent character and acidity increases. Mn₂O₇, CrO₃ are acidic and their lower oxides are basic and amphoteric. Stability of higher oxides increases down the group.

Q. 

Which of the following undergo disproportionation?

Matching List Type

Direction (Q. Nos. 18 and 19) Choices for the correct combination of elements from Column I and Column II are given as options (a), (b), (c) and (d), out of which one is correct.

Q.

Match the Column I with Column II and mark the correct option from the codes given below.

Match the Column I with Column II and mark the correct option from the codes given below.

During estimation of oxalic acid Vs KMnO₄, self indicator is-

50 cc of 0.04 M K₂Cr₂O₇ in acidic medium oxidises a sample of H₂S gas to sulphur. Volume of 0.03 M KMnO₄ required to oxidise the same amount of H₂S gas to sulphur in acidic medium is 10 x x. Here, the value of x is

The number of sigma bonds in ion are

If molarity of K₂Cr₂O₇ solution is 0.5 M, its normality value is

Statement Type

Direction (Q. Nos. 24 and 25) This section is based on Statement I and Statement II. Select the correct answer from the codes given below.

Q. 

Statement I ; When a solution of potassium chromate is treated with an excess of dilute nitric acid chromate undergoes oxidation.

Statement II : Dichromate ions are produced in above process.

Statement I : The oxidation state of chromium in the final product formed by the reaction between Kl and acidified potassium dichromate solution has green colour.

Statement II : The product has Cr³⁺ ions.