Valency and Oxidation State

Q.

What is the oxidation number of carbon in Carbon monoxide?

Q.

Find the oxidation number of $\mathrm{N}$ in${\mathrm{NH}}_4$ ion.

Q.

Oxidation number of oxygen atom in O₃ molecules is

1. 0

2. +2

3. +1

4. -1

Q.

What is the oxidation number of iodine in ${\mathrm{I}}_2$?

Q.

The oxidation number of cobalt in $\mathrm{K}\left[\mathrm{Co}{\left(\mathrm{CO}\right)}_4\right]$ is

1. $+1$

2. $+3$

3. $-1$

4. $-3$

Q.

What is the oxidation number of $\mathrm{O}$ in the ion ${\mathrm{OH}}^{-}$?

Q.

How do you find the oxidation number of $\mathrm{S}$ in${{\mathrm{SO}}_4}^{-2}$?

Q. Calculate the n-factor of $S_2{O}_3$ for the following change.
$2S_2{O}_3^{2-}\to S_4{O}_6^{2-}+2e^{-}$

1. 1
2. 0.5
3. 2
4. None of these

Q. 38. In case of CH3COOH, the oxidation number of carbon of carboxylic group is (1) 3 (2) Zero (3) +1 (4) +3

Q. For the given reaction :

$S_8\left(s\right)+12NaOH\left(aq\right)\to 4N{a}_{2}S\left(aq\right)+2N{a}_2{S}_2{O}_3\left(aq\right)+6H_{2}O\left(l\right)$
What will be the overall valence factor $\left(n_f\right)$ for $S_8$?

1. 16
2. 8
3. 5
4. 20

Q.

For $H_{3}P{O}_3$ and $H_{3}P{O}_4$ the correct choice is

1. H₃PO₃ is dibasic and reducing

2. H₃PO₃ is dibasic and non-reducing

3. H₃PO₄ is tribasic and reducing

4. H₃PO₃ is tribasic and non-reducing

Q. In case of CH3COOH the oxidation number of carbon of carboxylic group is

Q.

In the conversion

$N{H}_{2}OH⟶N_{2}O$

the equivalent weight of $N{H}_{2}OH$ will be

1. $\frac{M}{4}$

2. $\frac{M}{2}$

3. $\frac{M}{5}$

4. $\frac{M}{4}$

Q.

The oxidation number of Fe in K₄Fe(CN)₆ is

1. +6

2. +4

3. +3

4. +2

Q. Oxidation number of carbon in carbon suboxide, $\left(C_3{O}_2\right)$

1. $+\frac{2}{3}$
2. $+\frac{4}{3}$
3. $+\frac{4}{7}$
4. $+4$

Q. The oxidation number of oxygen in $K{O}_2$ is:

1. $-2$
2. $-\frac{1}{3}$
3. $-\frac{1}{2}$
4. $-1$

Q.

In which of the following compounds, is the oxidation number of iodine is fractional

1. IF3

2. IF2

3. IF7

4. I^-3

Q. On warming with silver powder, chloroform is converted into:

1. 1, 1, 2, 2-tetrachloroethane
2. ethylene
3. hexachloroethane
4. acetylene

Q. What will be the oxidation state of Hydrogen in $H_{2}S$ and $LiH$ respectively?

1. $+1$ and $-1$
2. $+0.5$ and $-0.5$
3. $-1$ and $+1$
4. $+2$ and $-1$

Q. Oxidation number of chlorine$\left(Cl\right)$ atoms in $HCl{O}_4$​ and $HCl{O}_3$​ molecules are :

1. $+7and-5$
2. $+6and+5$
3. $+7and-1$
4. $+7and+5$

Q. In which of the following pairs, the difference in the oxidation number of the mentioned element is highest ?

1. $S{O}_{2}andS{O}_3$ for $S$
2. $N{O}_{2}and{N}_2{O}_4$ for $N$
3. $P_2{O}_{5}and{P}_4{O}_{10}$ for $P$
4. 
   $N_{2}OandNO$ for $N$

Q. What will be the valence factor or n-factor $\left(n_f\right)$ for $H_{2}S{O}_4$ when
(i) It reacts with $NaOH$ to form $NaHS{O}_4$
(ii) It reacts with $NaOH$ to form $N{a}_{2}S{O}_4$

1. $n_f$ of $H_{2}S{O}_4$ is 2 for both the cases
2. (i) $n_f$ is $1$ and (ii) $n_f$ is $2$
3. $n_f$ of $H_{2}S{O}_4$ is 1 for both the cases
4. None of the above

Q. Which of the following compounds has/have the sulphur atom in its maximum oxidation state?
$x=H_{2}S{O}_4;y=H_{2}S{O}_5;z=H_2{S}_2{O}_8$

1. $z$ only
2. $y$ and $z$ only
3. $y$ only
4. $x,y$ and $z$

Q. Find the n-factor of $I^{-}$ in the given reaction $I^{-}\to ICl$ ?

1. -1
2. -2
3. 1
4. 2

Q. In case of CHCOOH, the oxidation number of carbon of carboxylic group is

Q. Find the n-factor of Cu and Zn for reduction of copper sulphate by Zinc ?

1. 2, 2
2. 1, 2
3. 2, 1
4. 0, 0

Q. Oxidation number of nitrogen "$N$" in $N_2{H}_5^{+}$​ is :

1. $-1$
2. $+3$
3. $-2$
4. $+1$

Q.

Which of the following is an example of reduction?

1. 

2. + 2

3. 

4. 

Q. What will be the n-factor $\left(n_f\right)$ for $F{e}_2{O}_3$ in the following chemical change :
$F{e}_2{O}_3\to FeS{O}_4$

1. $0$
2. $1$
3. $2$
4. $3$

Q. The equivalent weight of $MnS{O}_4$ is half its molecular weight when it is converted to
(IIT-JEE, 1988)

1. $M{n}_2{O}_3$
2. $Mn{O}_2$
3. $Mn{O}_4^{\ominus }$
4. $Mn{O}_4^{2-}$