Oxidation Number Method

Q. what volume of solution of HCL containing 73 gram per litre would sufficient gor the exact neutralization NaOH obtained by allowing 0.46g of metallic sodium to react with water.

Q. a solution of Naoh is 4gl^{-1} what volume of hcl gas at STP will neutralize 50ml of the alkali solutio

Q. 16. So2cl2 reacts with H2o gives H2so4 and Hcl determine volume of 0.2M Ba(oH)2 required to neutralised 25ml of 0.1 M so2cl2

Q. Which of the following doesnt reduce tollens solution? Catechol Phenol Resorcinol Quinol

Q. Match the reactions given in List I with the number of electrons lost or gained in List II
$\begin{array}{cccc}& Column-I& & Column-II\\ & Reaction& & Numberofelectronslostorgained\\ \left(P\right)& Mn(OH{)}_2+H_2{O}_2\to Mn{O}_2+2H_{2}O& \left(1\right)& 8\\ \left(Q\right)& AlC{l}_3+3K\to Al+3KCl& \left(2\right)& 2\\ \left(R\right)& 3Fe+4H_{2}O\to F{e}_3{O}_4+4H_2& \left(3\right)& 3\\ \left(S\right)& 3H_{2}S+2HN{O}_3\to 3S+2NO+4H_{2}O& \left(4\right)& 6\end{array}$

1. $\begin{array}{cccc}P& Q& R& S\\ 2& 3& 1& 4\end{array}$
2. $\begin{array}{cccc}P& Q& R& S\\ 3& 2& 1& 4\end{array}$
3. $\begin{array}{cccc}P& Q& R& S\\ 2& 1& 3& 4\end{array}$
4. $\begin{array}{cccc}P& Q& R& S\\ 1& 4& 3& 2\end{array}$

Q. Balance the following chemical equation:$\underset{\left(aq\right)}{C{r}_2{O}_7^{-2}}+\underset{\left(aq\right)}{S{O}_3^{-2}}\to \underset{\left(aq\right)}{C{r}^{+3}}+\underset{\left(aq\right)}{S{O}_4^{-2}}$ (Acidic medium)

1. $\underset{\left(aq\right)}{C{r}_2{O}_7^{-2}}+\underset{\left(aq\right)}{3S{O}_3^{-2}}+\underset{\left(aq\right)}{H^{+}}\to \underset{\left(aq\right)}{2C{r}^{+3}}+\underset{\left(aq\right)}{3S{O}_4^{-2}}+\underset{\left(aq\right)}{4H_{2}O}$
2. $\underset{\left(aq\right)}{C{r}_2{O}_7^{-2}}+\underset{\left(aq\right)}{S{O}_3^{-2}}+\underset{\left(aq\right)}{8H^{+}}\to \underset{\left(aq\right)}{2C{r}^{+3}}+\underset{\left(aq\right)}{3S{O}_4^{-2}}+\underset{\left(aq\right)}{4H_{2}O}$
3. $\underset{\left(aq\right)}{C{r}_2{O}_7^{-2}}+\underset{\left(aq\right)}{3S{O}_3^{-2}}+\underset{\left(aq\right)}{8H^{+}}\to \underset{\left(aq\right)}{2C{r}^{+3}}+\underset{\left(aq\right)}{3S{O}_4^{-2}}+\underset{\left(aq\right)}{4H_{2}O}$
4. $\underset{\left(aq\right)}{C{r}_2{O}_7^{-2}}+\underset{\left(aq\right)}{3S{O}_3^{-2}}+\underset{\left(aq\right)}{8H^{+}}\to \underset{\left(aq\right)}{C{r}^{+3}}+\underset{\left(aq\right)}{3S{O}_4^{-2}}+\underset{\left(aq\right)}{4H_{2}O}$

Q.

In which of the following has the oxidation number of oxygen been arranged in increasing order?

1. BaO₂< KO₂< O₃< OF₂

2. OF₂< KO₂< BaO₂< O₃

3. BaO₂< O₃< OF₂< KO₂

4. KO₂< OF₂< O₃< BaO₂

Q. Balance the following redox reaction in basic medium:
$Cl{O}^{-}+Cr{O}_2^{-}\to C{l}^{-}+Cr{O}_4^{2-}$

1. $2Cl{O}^{-}+3Cr{O}_2^{-}+2O{H}^{-}\to 3C{l}^{-}+Cr{O}_4^{2-}+2H_{2}O$
2. $3Cl{O}^{-}+2Cr{O}_2^{-}+2O{H}^{-}\to 3C{l}^{-}+2Cr{O}_4^{2-}+H_{2}O$
3. $Cl{O}^{-}+2Cr{O}_2^{-}+3O{H}^{-}\to 2C{l}^{-}+3Cr{O}_4^{2-}+2H_{2}O$
4. $3Cl{O}^{-}+2Cr{O}_2^{-}+O{H}^{-}\to 3C{l}^{-}+3Cr{O}_4^{2-}+2H_{2}O$

Q. The number of moles of $KMn{O}_4$ that will be needed to react completely with one mole of ferrous oxalate in an acidic solution is:

1. $\frac{3}{5}$
2. $\frac{2}{5}$
3. $\frac{4}{5}$
4. $\frac{1}{5}$

Q. The reaction of the permanganate ion with the oxalate ion in acidic solution forms manganese(II) ion and carbon dioxide. What is the stoichiometric coefficient in front of manganese(II) in the balanced redox equation?
$Mn{O}_4^{-}+C_2{O}_4^{2-}\to M{n}^{2+}+C{O}_2$

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

Q. The given unbalanced redox reaction
$S_2{O}_3^{2-}+S{b}_2{O}_5+H^{+}\to SbO+H_{2}S{O}_3$
is balanced by oxidation number method. The stoichiometric coefficient of $S{b}_2{O}_5$ and $SbO$ respectively, will be:

1. $2,4$
2. $4,8$
3. $3,6$
4. $1,2$

Q.

N factor for the reaction (BrO3-) + (Br-)= Br2

Q. What would be the value of stoichiometric coefficients of $Mg$ and $V{O}_4^{3-}$ respectively, in the balanced net ionic equation for the given redox reaction in acidic medium:
$Mg\left(s\right)+V{O}_4^{3-}\left(aq\right)\to M{g}^{2+}\left(aq\right)+V^{2+}\left(aq\right)$

1. 3, 2
2. 8, 16
3. 1, 1
4. 5, 10

Q. What will be the correct balanced redox reaction for the given equation? (Use oxidation number method)
$T{l}_2{O}_3\left(s\right)+N{H}_{2}OH\left(aq\right)\to TlOH\left(s\right)+N_2\left(g\right)$

1. $T{l}_2{O}_3\left(s\right)+2N{H}_{2}OH\left(aq\right)\to 2TlOH\left(s\right)+N_2\left(g\right)+5H_{2}O$
2. $2T{l}_2{O}_3\left(s\right)+4N{H}_{2}OH\left(aq\right)\to 4TlOH\left(s\right)+2N_2\left(g\right)+5H_{2}O$
3. $T{l}_2{O}_3\left(s\right)+4N{H}_{2}OH\left(aq\right)\to 2TlOH\left(s\right)+2N_2\left(g\right)+5H_{2}O$
4. $T{l}_2{O}_3\left(s\right)+2N{H}_{2}OH\left(aq\right)\to 2TlOH\left(s\right)+N_2\left(g\right)+5H_{2}O$

Q. In the following reaction :

$H_2{O}_2\left(aq\right)+C{l}_2{O}_7\left(aq\right)\to Cl{O}_2^{-}\left(aq\right)+O_2\left(g\right)$

calculate the moles of $O{H}^{-}$ and $H_{2}O$ respectively present in a balanced equation in a basic medium :

1. 3, 6
2. 4, 6
3. 2, 5
4. 4, 4

Q. Consider the following redox reaction:
$Mn\left(OH{)}_2\right(s)+Mn{O}_4^{-}(aq)\to Mn{O}_2(s)$
If $x,y,z$ are the stoichiometric coefficients of $Mn(OH{)}_2,Mn{O}_4^{-}$ and $Mn{O}_2$ respectively when the above reaction is balanced in basic medium.
What will be the value of $x+y+z$ ?

1. 5
2. 8
3. 10
4. 12

Q. The oxidation state of $Fe$ in ${Fe}_3{O}_8$ is :

1. $\frac{4}{5}$
2. $\frac{5}{4}$
3. $\frac{3}{2}$
4. $\frac{16}{3}$

Q. How do you form an equation for such problems?
Q.54. When potassium permanganate is titrated against ferrous ammonium sulphate, the equivalent weight of ferrous ammonium sulphate is:
(a) M
(b) M / 2
(c) M / 5
(d) M / 3

Q. Consider a redox reaction :

$xN{a}_{2}HAs{O}_3+yNaBr{O}_3+zHCl\to NaBr+H_{3}As{O}_4+NaCl$

where $x,y,z$ are the stoichiometric coefficients of $N{a}_{2}HAs{O}_3,NaBr{O}_3,HCl$ respectively.
The value of $x+y+z$ in the above balanced redox reaction is :

1. $3$
2. $9$
3. $10$
4. $12$

Q.

How many $H_{2}O$ should be added to the RHS of the following equation to balance number of oxygen atoms on the left ?

$6F{e}^{2+}+C{r}_2{O}_7^{2-}+14H^{+}⟶6F{e}^{3+}+2C{r}^{3+}+$ ___________

1. 2

2. 4

3. 5

4. 7

Q. The number of moles of $KMn{O}_4$ that will be needed to react completely with 1 mole of ferrous oxalate in acidic medium is

Q. Find the equivalent weight of $C{r}_2{O}_7^{2-}$ in the given reaction, if the molar mass of $C{r}_2{O}_7^{2-}$ is 'M' ?
$C{r}_2{O}_7^{2-}\stackrel{H^{+}}{\to }C{r}^{3+}$

1. $\frac{M}{3}$
2. $M$
3. $\frac{M}{6}$
4. $2M$

Q. Which of the following equations is a balanced one?

1. $2Bi{O}_3^{-}+4H^{+}+M{n}^{2+}\to 2B{i}^{3+}+2H_{2}O+Mn{O}_4^{-}$
2. $5Bi{O}_3^{-}+14H^{+}+2M{n}^{2+}\to 5B{i}^{3+}+7H_{2}O+2Mn{O}_4^{-}$
3. $5Bi{O}_3^{-}+22H^{+}+M{n}^{2+}\to 5B{i}^{3+}+7H_{2}O+Mn{O}_4^{-}$
4. $6Bi{O}_3^{-}+12H^{+}+3M{n}^{2+}\to 6B{i}^{3+}+6H_{2}O+3Mn{O}_4^{-}$