Types of Redox Reactions

Q.

Define oxidation and oxidising agent.

Q.

Which of the following reaction is an example of a redox reaction?

1. ${\mathrm{XeF}}_6+{\mathrm{H}}_2\mathrm{O}\to {\mathrm{XeOF}}_4+2\mathrm{HF}$

2. ${\mathrm{XeF}}_4+{\mathrm{O}}_2{\mathrm{F}}_2\to {\mathrm{XeF}}_6+{\mathrm{O}}_2$

3. ${\mathrm{XeF}}_2+{\mathrm{PF}}_5\to {\left[\mathrm{XeF}\right]}^{+}+{{\mathrm{PF}}_6}^{-}$

4. ${\mathrm{XeF}}_6+2{\mathrm{H}}_2\mathrm{O}\to {\mathrm{XeO}}_2{\mathrm{F}}_2+4\mathrm{HF}$

Q. $P_4+3NaOH+3H_{2}O⟶3Na\left(H_{2}P{O}_2\right)+P{H}_3$ is an example of a reaction.

1. disproportionation
2. pyrolytic
3. neutralisation

Q. $F{e}^{3+}$ is reduced to $F{e}^{2+}$ by using

1. $H_2{O}_2$ in presence of $NaOH$
2. $N{a}_2{O}_2$ in water
3. $H_2{O}_2$ in presence of $H_{2}S{O}_4$
4. $N{a}_2{O}_2$ in presence of $H_{2}S{O}_4$

Q. Calculate the volume of 0.015 M HCl solution required to prepare 250 mL of a $5.25\times {10}^{-3}$ M HCl solution.

1. 63.4 mL
2. 26.4 mL
3. 28.0 mL
4. 87.5 mL

Q. What volume of 12.5 M concentrated HCl is required to make 1 L of 0.1 M HCl solution?

1. 7 mL
2. 9 mL
3. 8 mL
4. 10 mL

Q.

Explain the given reactions with the examples (a) Hydrogenation reaction (b) Oxidation reaction (c) Substitution reaction (d) Saponification reaction (e) Combustion reaction.

Q. The reaction, $3Cl{O}^{-}\left(aq\right)⟶Cl{O}_3^{-}\left(aq\right)+2C{l}^{-}\left(aq\right)$ is an example ofreaction.

1. Oxidation
2. Reduction
3. Disproportionation
4. Decomposition

Q. How much water should be added to 750 mL of a 2.8 M HCl solution to make a 1.0 M resultant solution?

1. 0.75 L
2. 1.25 L
3. 1.35 L
4. 1.00 L

Q.

When iron is rusted, it is:

1. Oxidized

2. Reduced

3. Evaporated

4. Decomposed

Q. The equilibrium constant for the following reaction is ${10}^{30}$. Calculate $E^{\circ }$ (in volts) for the cell at 298 K.
$2X_2\left(s\right)+3Y^{2+}\left(aq\right)$→$2X_2^{3+}\left(aq\right)+3Y\left(s\right)$

1. +0.105 V
2. +0.295 V
3. +0.0985 V
4. -0.295 V

Q.

The fast reaction between water and sodium is an example of:

1. Reduction

2. Oxidation

3. Intramolecular redox

4. Intermolecular redox

Q. In the Kjedahl's method for estimation of nitrogen present in soil sample, ammonia evolved from 0.75 g of sample neutralized 10 ml. of $1M{H}_{2}S{O}_4$. The percentage of nitrogen in the soil is:

1. $37.33$
2. $35.33$
3. $445.33$
4. $43.33$

Q.

In the reaction $2Mg+C{O}_2\to 2MgO+C$, oxidizing and reducing agents are, respectively, _______ and ___________.

Q. Which of the following is not an example of redox reaction?

1. $CuO+H_2\to Cu+H_{2}O$
2. $F{e}_2{O}_3+3CO\to 2Fe+3C{O}_2$
3. $2K+F_2\to 2KF$
4. $BaC{l}_2+H_{2}S{O}_4\to BaS{O}_4+2HCl$

Q. Consider the change in oxidation state of Bromine corresponding to different emf values as shown in the diagram below :

Then the species undergoing disproportionation is:

1. $B{r}_2$
2. $Br{O}_4^{-}$
3. $Br{O}_3^{-}$
4. $HBrO$

Q.

$P_4+3NaOH+3H_{2}O⟶3Na\left(H_{2}P{O}_2\right)+P{H}_3$ is an example of:

1. Disproportionation reaction

2. Neutralisation reaction

3. Double decomposition reaction

4. Pyrolytic reaction

Q.

When $KMn{O}_4$ acts as an oxidising agent and ultimately forms $[Mn{O}_4{]}^{-2},Mn{O}_2,M{n}_2{O}_3,M{n}^{+2}$ then the number of electrons transferred in each case respectively is

1. 4, 3, 1, 5

2. 1, 5, 3, 7

3. 1, 3, 4, 5

4. 3, 5, 7, 1

Q. During the disproportionation of Iodine to iodide and iodate ions, the ratio of iodate and iodide ions formed in alkaline medium is:

$I_2\to I{O}_3^{-}+I^{-}$

1. 1 : 5
2. 5 : 1
3. 3 : 1
4. 1 : 3

Q. For the given disproportionation reaction:
$H_{3}P{O}_2\to P{H}_3+H_{3}P{O}_3$
The equivalent mass of $H_{3}P{O}_2$ is :
Given : $\text{Atomic mass of}P=31u$

1. $33g$
2. $66g$
3. $49.5g$
4. $16.5g$

Q. What will be the overall n-factor for the given disproportionation reaction:
$2CuBr\left(aq\right)\to CuB{r}_2\left(aq\right)+Cu\left(s\right)$

Q.

The reaction, $3Cl{O}^{-}\left(aq\right)⟶Cl{O}_3^{-}\left(aq\right)+2C{l}^{-}\left(aq\right)$ is an example of:

1. Oxidation reaction

2. Reduction reaction

3. Disproportionation Reaction

4. Decomposition reaction

Q.

Define the term decomposition reaction.

Q.

Three moles of hypochlorite gives 2 moles of chloride and one mole of chlorate. This is:

1. Oxidation reaction

2. Reduction reaction

3. Disproportionation reaction

4. Decomposition reaction

Q. For the given disproportionation reaction:
$H_{3}P{O}_2\to P{H}_3+H_{3}P{O}_3$
The equivalent mass of $H_{3}P{O}_2$ in grams is :
(Given : $\text{Atomic mass of}P=31u$)

Q. Which of the following is not an intramolecular redox reaction?

1. $2KCl{O}_3\to 2KCl+3O_2$
2. $2M{n}_2{O}_7\to 4Mn{O}_2+3O_2$
3. $2H_2{O}_2\to 2H_{2}O+O_2$
4. None of the above

Q. Equivalent weight of $H_{3}P{O}_2$ when it disproportionates into $P{H}_3$ and $H_{3}P{O}_3$ is:

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

Q. Which of the following are displacement reactions?

1. $Cu\left(s\right)+2AgN{O}_3\left(aq\right)⟶2Ag\left(s\right)+Cu\left(N{O}_3{)}_2\right(aq)$
2. $Ca\left(s\right)+2H_{2}O\left(l\right)⟶2NaOH\left(aq\right)+H_2\left(g\right)$
   
3. $2Pb\left(N{O}_3{)}_2\right(s)\to 2PbO(s)+2N{O}_2(g)+\frac{1}{2}{O}_2(g)$
4. $N_2\left(g\right)+O_2\left(g\right)\to 2NO\left(g\right)$

Q. In the reaction,
$3B{r}_2+6C{O}_3^{2-}+3H_{2}O\to 5B{r}^{-}+Br{O}_3^{-}+6HC{O}_3^{-}$

1. bromine is oxidized and carbonate is reduced
   
2. bromine is oxidized
   
3. bromine is reduced
   
4. It is a disproportionation reaction

Q. The reaction, $3Cl{O}^{-}(aq.)\to Cl{O}_3^{-}(aq.)+2C{l}^{-}(aq.)$ is an example of :

1. Oxidation reaction
2. Reduction reaction
3. Disproportionation reaction
4. Decomposition reaction