101.
The oxidation state of nitrogen is correctly given for
A
(i)
B
(ii)
C
(iii)
D
(iv)
Answer :
(iv)
102. The standard $${E^ \circ }$$ values of few redox couples are $$\frac{{Z{n^{2 + }}}}{{Zn}} = - 0.76\,V,\frac{{A{g^ + }}}{{Ag}} = + 0.80\,V,$$ $$\frac{{C{u^{2 + }}}}{{Cu}} = 0.34\,V.$$ Choose the correct option.
A
$$Cu$$ can oxidise $$Zn$$ and $$Ag.$$
B
$$Ag$$ can reduce $$Z{n^{2 + }}$$ and $$C{u^{2 + }}.$$
C
$$Zn$$ can reduce $$A{g^ + }$$ and $$C{u^{2 + }}.$$
D
$$Cu$$ can reduce $$Z{n^{2 + }}$$ and $$A{g^ + }.$$
Answer :
$$Zn$$ can reduce $$A{g^ + }$$ and $$C{u^{2 + }}.$$
103. Which of the following is a decreasing order of oxidation states of the central atoms?
A
$$PC{l_5},HI{O_4},C{r_2}O_7^{2 - },C{O_2}$$
B
$$C{r_2}O_7^{2 - },C{O_2},HI{O_4},PC{l_5}$$
C
$$HI{O_4},C{r_2}O_7^{2 - },PC{l_5},C{O_2}$$
D
$$C{r_2}O_7^{2 - },HI{O_4},C{O_2},PC{l_5}$$
Answer :
$$HI{O_4},C{r_2}O_7^{2 - },PC{l_5},C{O_2}$$
104. The oxidation number of $$Pt$$ in $${\left[ {Pt\left( {{C_2}{H_4}} \right)C{l_3}} \right]^ - }$$ is
A
$$+1$$
B
$$+2$$
C
$$+3$$
D
$$+4$$
Answer :
$$+2$$
105. Which of the following reactions will not take place at cathode?
A
$$A{g^ + } \to Ag - {e^ - }$$
B
$$F{e^{2 + }} \to F{e^{3 + }} + {e^ - }$$
C
$$C{u^{2 + }} + 2{e^ - } \to Cu$$
D
$$A{l^{3 + }} \to Al - 3{e^ - }$$
Answer :
$$F{e^{2 + }} \to F{e^{3 + }} + {e^ - }$$
106.
Consider the following reaction,
Select the incorrect statement.
A
It is not a disproportionation reaction.
B
It is intramolecular redox reaction.
C
$$O{H^ - }$$ is a reducing as well as oxidising agent.
D
is a reducing as well as oxidising agent.
is a reducing as well as oxidising agent.
Answer :
$$O{H^ - }$$ is a reducing as well as oxidising agent.
is reducing as well as oxidising agent.107. Which of the following involves transfer of five electrons ?
A
$$MnO_4^ - \to M{n^{2 + }}$$
B
$$CrO_4^{2 - } \to C{r^{3 + }}$$
C
$$MnO_4^{2 - } \to Mn{O_2}$$
D
$$C{r_2}O_7^{2 - } \to 2C{r^{3 + }}$$
Answer :
$$MnO_4^ - \to M{n^{2 + }}$$
108.
Indicate whether the following conversions represent an oxidation, a reduction or none ( neither oxidation nor reduction ).
$$\eqalign{
& \left( {\text{i}} \right)HC{l_3}\,\,{\text{to}}\,\,HCl{O_4} \cr
& \left( {{\text{ii}}} \right)NH_4^ + \,{\text{to}}\,N{H_3} \cr
& \left( {{\text{iii}}} \right)N{O_2}\,\,{\text{to}}\,\,{N_2}{O_4} \cr
& \left( {{\text{iv}}} \right)HSO_3^ - \,{\text{to}}\,\,SO_4^{2 - } \cr
& \left( {\text{v}} \right){H_2}{O_2}\,\,{\text{to}}\,\,{H_2}O \cr} $$
| (i) | (ii) | (iii) | (iv) | (v) | |
| (a) | Oxidation | Reduction | None | None | Oxidation |
| (b) | Oxidation | None | None | Oxidation | Reduction |
| (c) | Reduction | Oxidation | Reduction | None | Reduction |
| (d) | Oxidation | Reduction | None | Reduction | Reduction |
A
(a)
B
(b)
C
(c)
D
(d)
Answer :
(b)
109. The oxidation number of $$Fe$$ in $$N{a_2}\left[ {Fe{{\left( {CN} \right)}_5}NO} \right]$$ is
A
$$+2$$
B
$$+1$$
C
$$+3$$
D
$$-2$$
Answer :
$$+2$$
110. The oxidation state of $$Fe$$ in $$F{e_3}{O_8}$$ is
A
$$\frac{3}{2}$$
B
$$\frac{4}{5}$$
C
$$\frac{5}{4}$$
D
$$\frac{{16}}{3}$$
Answer :
$$\frac{{16}}{3}$$