D & f- BLOCK ELEMENTS practice · Mixed difficulty

Assertion: The more number of oxidation states are exhibited by the actinoids than by the Lanthanoids.

Reason: There is a lesser energy difference between $5 {f}$ and $6 {~d}$ orbitals than that between $4 {f}$ and $5 {~d}$ orbitals.

Element of most positive value of ${E}_{{M}^{3+} / {M}^{2+}}^{\circ}$ among the following is

Among Sc(III), Ti(IV), Pd(II) and Cu(II) ions

The composition of bell metal is

Assertion : ${\text{C}}{{\text{e}}^{ + 4}}$ acts as oxidising agent in aqueous medium

Reason : $+4$ is common oxidation state of lanthanides

$\mathrm{Cr}_2 \mathrm{O}_7^{2-}+\mathrm{xH}^{+}+\mathrm{ye}^{-} \rightarrow 2 \mathrm{Cr}^{3+}+\mathrm{AH}_2 \mathrm{O}$
Balance the above reaction and find $\mathrm{x, y}$ and $\mathrm{A}$.

Which of the following conversions can be carried out by both acidified $\mathrm{K}_2 \mathrm{Cr}_2 \mathrm{O}_4$ and acidified $\mathrm{KMnO}_4$ ?

(i) $\mathrm{Fe}^{2+} \rightarrow \mathrm{Fe}^{3+}+\mathrm{e}^{-}$

(ii) $\mathrm{I}^{-} \rightarrow \mathrm{IO}_3^{-}$

(iii) $\mathrm{I}^{-} \rightarrow \mathrm{I}_2$

(iv) $\mathrm{H}_2 \mathrm{~S} \rightarrow \mathrm{S}$

Metal are generally hard, opaque, shiny and good conductor of heat and electricity. Which of the following elements has highest density?

In the equation,

$4M\mathrm{\;} + \mathrm{\;}8\mathrm{C}{\mathrm{N}^ - }\mathrm{\;} + \mathrm{\;}2{\mathrm{H}_2}\mathrm{O\;} + \mathrm{\;}{\mathrm{O}_2}\mathrm{\;\;} \to \mathrm{\;}4{\left[ {M{{\left( {\mathrm{CN}} \right)}_2}} \right]^ - }\mathrm{\;} + \mathrm{\;}4\mathrm{O}{\mathrm{H}^ - }$

Identify the metal $M$

The maximum number of possible oxidation states of actinoides are shown by

What is the oxidation state of iron in Mohr’s salt?

When mercury (I) chloride is heated and the vapour so evolved are cooled, the substance on sublimation thus collected consists of

Which is the correct order of ionic sizes?) At.no.∶Ce=58,Sn=50,Yb=70 and Lu=71)

Which among the following metals does not dissolve in aqua regia?

Which of the following does not involve $d \rightarrow d$ transition for causing colour ?

Observe the following statements
1) Lanthanides actively participate in chemical reactions
2) The basic nature of hydroxides of lanthanides increases from $La{\left( {OH} \right)_3}$ to $Lu{\left( {OH} \right)_3}$
3) Most stable oxidation number shown by Lanthanides is + 3
The correct statements are

Chromium is used in making:

The oxidation number of Mn in the product of alkaline oxidative fusion of $\mathrm{Mn}{\mathrm{O}_2}$ is

Correct outer electronic configuration of trivalent cationic form of ${Np}$ (Neptunium, atomic number of 93 ) is

Most common oxidation state of $\mathrm{Mn}$ (atomic No: $25)$ is

Zn cannot displace the following ions from their aqueous solutions:

Which of the following statements is not true?

Assertion : Zr and Hf have about the same atomic radius.

Reason: Zr and Hf lies in the same group.

Which is used for electrical purposes?

The compound which gives oxygen on moderate heating is:

Alloys of which metal are light and strong and are used in the manufacture of aeroplanes?

In haemoglobin the iron shows oxidation state :

In order to prepare one litre $1 \mathrm{~N}$ solution of ${KMnO}_4$, how many grams of ${KMnO}_4$ are required, if the solution to be used in acid medium for oxidation?

The first man-made atom is:

Given below are two statements: One is labelled as Assertion A and the other is labelled as Reason R.
Assertion A: Permanganate titrations are not performed in presence of hydrochloric acid.
Reason R: Chlorine is formed as a consequence of oxidation of hydrochloric acid.
In the light of the above statements, choose the correct answer from the options given below.