Embibe Experts Solutions for Chapter: Redox Reactions, Exercise 4: Exercise-4

Which of the following elements can have negative oxidation states.

The oxidation state of Cr in ${\mathrm{K}}_2\mathrm{C}{\mathrm{r}}_2{\mathrm{O}}_7$ is

Oxidation number of $\mathrm{Mn}$ in ${{\mathrm{MnO}}_4}^{-}$ ion is:

Which of the following disproportionate(s) on heating with sodium hydroxide?
 

The correct balanced chemical equation for the reaction between $\mathrm{Al}$ and $\mathrm{S}$ is :

Given the ${\mathrm{E}}_0$ values for the half reactions:

${\mathrm{Sn}}^{4+}+2{\mathrm{e}}^{-}\to {\mathrm{Sn}}^{2+},0.15\mathrm{V}$
$2{\mathrm{Hg}}^{2+}+2{\mathrm{e}}^{-}\to {\mathrm{Hg}}_2^{2+},0.92\mathrm{V}$
${\mathrm{PbO}}_2+4{\mathrm{H}}^{+}+2{\mathrm{e}}^{-}\to {\mathrm{Pb}}^{2+}+2{\mathrm{H}}_2\mathrm{O},1.45\mathrm{V}$
Which of the following statements is true?

For the decomposition of ${\mathrm{H}}_2{\mathrm{O}}_2\left(\mathrm{aq}\right)$ it was found that ${\mathrm{V}}_{{\mathrm{O}}_2}\left(\mathrm{t}=15 \min .\right)$ was $100 \mathrm{mL}$ (at $0°\mathrm{C}$ and $1 \mathrm{atm}$) while ${\mathrm{V}}_{{\mathrm{O}}_2}$ (maximum) was $200 \mathrm{mL}$ (at $0°\mathrm{C}$ and $2 \mathrm{atm}$). If the same reaction had been followed by the titration method and if ${\mathrm{V}}_{{\mathrm{KMnO}}_4}^{\left(\mathrm{cM}\right)}\left(\mathrm{t}=0\right)$ had been $40 \mathrm{mL},$ what would ${\mathrm{V}}_{{\mathrm{KMnO}}_4}^{\left(\mathrm{cM}\right)}\left(\mathrm{t}=15 \min \right)$ have been?

Which of the following cannot act as an oxidising agent?