Variable Oxidation States

Q.

How does the oxidation state of the element differ as compared to its place in the periodic table?

Q. When $AgN{O}_3$ is treated with hypo solution, a white ppt of A is formed. This gets dissolved when excess of hypo solution is added due to the formation of compound B. Precipitate A on boiling with water turns black due to the formation of C. Find the incorrect option:

1. White precipitate is due to $N{a}_3\left[Ag\right(S_2{O}_3{)}_2]$
2. Black precipitate is due to $A{g}_{2}S$
3. Along with $C$, $H_{2}S{O}_4$ is also formed
4. Average oxidation state of $S$ in hypo solution is $+2$

Q. Which is the most common oxidation state of lanthanides and actinide series?

1. +3 and +4
2. +2 and +3
3. +3 only
4. +2 only

Q.

The pair of compounds having metals in their highest oxidation state is

1. MnO₂, FeCl₃

2. MnO^-₄, CrO₂Cl₂

3. [Fe(CN)₆]^3-, [Co(CN)₄]

4. [NiCl₄]^2-, [CoCl₄]^-

Q. Which of the following compounds is least stable?

1. $PbC{l}_4$
2. $AgCl$
3. $SnC{l}_4$
4. $ZnC{l}_2$

Q. What is the oxidation number of $Cl$ in $CaOC{l}_2$?

1. 1
2. -1
3. \N
4. -2

Q. The d-electron configuration of $C{r}^{2+},M{n}^{2+},F{e}^{2+}\text{and}C{o}^{2+}$ are $d^4$, $d^5$, $d^6$ and $d^7$ respectively. Which one of the following will exhibit minimum paramagnetic behaviour? (Atomic number of Cr=24, Mn=25, Fe =26, Co=27)

1. $C{r}^{2+}$

2. $F{e}^{2+}$

3. $M{n}^{2+}$

4. $C{o}^{2+}$

Q. Zn reacts with dilute $HN{O}_3,Conc.HN{O}_3$ and very dilute $HN{O}_3$. The oxidation number of nitrogen changes from $HN{O}_3$ are $a,b,c$ in product $X,Y,Z$ respectively. What is the value of $(a+b+c)$ is
(a) $Zn+HN{O}_3\to Zn(N{O}_3{)}_2+"X"+H_{2}O$
dilute ($20\%$)
(b) $Zn+HN{O}_3\to Zn(N{O}_3{)}_2+"Y"+H_{2}O$
Conc ($70\%$)
(a) $Zn+HN{O}_3\to Zn(N{O}_3{)}_2+"Z"+H_{2}O$
very dilute ($6\%$)

Q. The oxidation states of Cr in $\left[Cr\right(H_{2}O{)}_{6}C{l}_3],[Cr\left(C_6{H}_6{)}_2\right]$ and $K_2\left[Cr\right(CN{)}_2\left(O{)}_2\right(O_2\left)\right(N{H}_3\left)\right]$ respectively are:

1. +3, 0, +4
2. +3, +4, +6
3. +3, +2, +4
4. +3, 0, +6

Q. The compound that do not act as oxidising agents among the following is/are

1. $Cr{O}_3$
2. $Mo{O}_3$
3. $W{O}_3$
4. $Cr{O}_4^{2-}$

Q. The element with electronic configuration $1s^{2}2s^{2}2p^5$ represents a non-metal.

1. False
2. True

Q.

The electrons which take part in order to exhibit variable oxidation states by transition metals are:

1. ns only

2. ns and (n-1)d only but not np

3. (n-1)d only

4. (n-1)d and np only but not ns

Q. Which of the following are true regarding oxidation states of transition elements?

1. d-block elements have variable oxidation state
2. d-block elements have zero oxidation state
3. d-block elements have only +1 oxidation state
4. d-block elements have only +2 oxidation state

Q. The equilibrium $P_4\left(s\right)+6C{l}_2\left(g\right)\leftrightharpoons 4PC{l}_3\left(g\right)$ Is attained by mixing equal moles of $P_{4}andC{l}_2$ inana evacuated vessel. Then at equilibrium

1. $\left[C{l}_2\right]>\left[PC{l}_3\right]$
2. $\left[C{l}_2\right]>\left[P_4\right]$
3. $\left[P_4\right]>\left[C{l}_2\right]$
4. $\left[PC{l}_3\right]>\left[P_4\right]$

Q. The electronic configuration $3p^6,3d^9$ represents a

1. Metal
2. Non-metal
3. Non-metallic anion
4. Metallic cation

Q. Zn reacts with dilute $HN{O}_3,Conc.HN{O}_3$ and very dilute $HN{O}_3$. The oxidation number of nitrogen changes from $HN{O}_3$ are $a,b,c$ in product $X,Y,Z$ respectively. What is the value of $(a+b+c)$ is
(a) $Zn+HN{O}_3\to Zn(N{O}_3{)}_2+"X"+H_{2}O$
dilute ($20\%$)
(b) $Zn+HN{O}_3\to Zn(N{O}_3{)}_2+"Y"+H_{2}O$
Conc ($70\%$)
(a) $Zn+HN{O}_3\to Zn(N{O}_3{)}_2+"Z"+H_{2}O$
very dilute ($6\%$)

Q. When $AgN{O}_3$ is treated with hypo solution, a white ppt of A is formed. This gets dissolved when excess of hypo solution is added due to the formation of compound B. Precipitate A on boiling with water turns black due to the formation of C. Find the incorrect option:

1. White precipitate is due to $N{a}_3\left[Ag\right(S_2{O}_3{)}_2]$
2. Black precipitate is due to $A{g}_{2}S$
3. Along with $C$, $H_{2}S{O}_4$ is also formed
4. Average oxidation state of $S$ in hypo solution is $+2$

Q. The correct order of N-compounds in its decreasing order of oxidation states is

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1. $HN{O}_3,NO,N_2,N{H}_{4}Cl$
2. $HN{O}_3,NO,N{H}_{4}Cl,N_2$
3. $N{H}_{4}Cl,N_2,NO,HN{O}_3$
4. $HN{O}_3,N{H}_{4}Cl,NO,N_2$

Q. Which of the following are oxidation states that copper exhibits?

1. +1 and +3
2. +1 and +2
3. +1, +2 and +3
4. +1, +2 and +4