Redox Reactions and Couple

Q. $S_8+bO{H}^{-}\to c{S}^{2-}+s{S}_2{O}_3^{2-}+H_{2}O$. Find the value of c.

Q. What is the oxidation state of Mn in Manganese (VII) oxide?

1. 1
2. 5
3. 3
4. 7

Q. The Oxidation state of Mn in $K_{2}Mn{O}_4$ is

1. 2
2. -2
3. 7
4. 6

Q. $KMn{O}_4$ acts as an oxidising agent in the neutral medium and gets reduced to $Mn{O}_2$.The equivalent weight of $KMn{O}_4$ in neutral medium

1. mol. wt/4
2. mol .wt/7
3. mol. wt/2
4. mol.wt/3

Q. Oxidation state of S in $N{a}_2{S}_2{O}_3$ is

1. 5
2. -1
3. 0
4. 2

Q. Oxidation state of S in $[HS{O}_4{]}^{-}$ is

1. 2
2. 4
3. 6
4. -2

Q. Oxidation state of O in $O{F}_2$ Is

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

Q. Oxidation number is not equal to number of electrons accepted or donated by an atom.

1. True
2. False

Q. Consider the half-cell reaction(s)
${Cu}^{2+}+e^{-}\to {Cu}^{+};E^o=0.15V$
${Cu}^{2+}+2e^{-}\to Cu;E^o=0.33V$
$E^o$ for the half-cell reaction: ${Cu}^{+}+e^{-}\to Cu$ will be:

1. $0.48V$
2. $0.18V$
3. $0.31V$
4. $0.51V$

Q. Among the following, identify the correct statement?

1. Chloride ion is oxidized by $O_2$
2. $F{e}^{2+}$ is oxidized by iodine
3. Iodide ion is oxidized by chlorine
4. $M{n}^{2+}$ is oxidized by chlorine