D & f- BLOCK ELEMENTS practice · Medium

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

$\mathrm{Cr}_2 \mathrm{O}_7^{2-}+\mathrm{xH}^{+}+\mathrm{ye}^{-} \rightarrow 2 \mathrm{Cr}^{3+}+\mathrm{AH}_2 \mathrm{O}$
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

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

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.

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?

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.

Silver nitrate is usually supplied in coloured bottles because it is:

Zn does not show variable valency because of

Metals generally melt at very high temperature. Amongst the following, the metal with the highest melting point will be

Assertion: Actinoids show more variety in oxidation state than lanthanoids.

Reason: Actinoids have comparatively larger size than lanthanoids.

In the chemical reaction,

${K}_2 {Cr}_2 {O}_7+{XH}_2 {SO}_4+{YSO}_2 \rightarrow {K}_2 {SO}_4+{Cr}_2\left({SO}_4\right)_3+{ZH}_2 {O}\,\,\, {X}, {Y}$ and ${Z}$ are

Case hardening

The number of ions from the following that are expected to behave as oxidising agent is:

$\mathrm{Sn}^{4+}, \mathrm{Sn}^{2+}, \mathrm{Pb}^{2+}, \mathrm{Tl}^{3+}, \mathrm{Pb}^{4+}, \mathrm{Tl}^{+}$

To an acidified dichromate solution, a pinch of ${Na}_2 {O}_2$ is added and shaken. Which of the following is observed?

Which is used for stopping bleeding?