Name: Understanding Silicate and Its Uses
Uploaded: 2019-07-19
Duration: 9 min 26 s
Description: Do you know that silicates are used to make glass and ceramics? It also plays a vital role in our daily life. Let's learn how it simplifies our lives.

Question

How many compound(s) or ion(s) can be oxidised by $H_{2} O_{2}$ among the following:

$(i)$ ${AsO}_{3}^{3 -}$

$(ii)$ ${SO}_{4}^{2 -}$

$(iii)$ ${Fe}_{2} {({SO}_{4})}_{3}$

$(iv)$ ${NH}_{2} - {NH}_{2}$

$(v)$ $H_{2} S$

$(vi)$ $PbS$

$(vii)$ $O_{3}$

Accepted Answer

In this question we are asked to find out which can be oxidised by $H_{2} O_{2}$ so, let's solve one by one

$(i)$ $H_{2} O_{2} + {AsO}_{3}^{3 -} \to {AsO}_{4}^{3 -} + H_{2} O$

Arsenite can be oxidized with $H_{2} O_{2}$ here, in arsenite ion arsenic has oxidation number is $(v)$ and in arsenate ion oxidation number of arsenic is $+ 5$ so ${AsO}_{3}^{- 3}$

So, this can be oxidised.

$O_{3}$ ${SO}_{4}^{- 2}$ can not be oxidised with $H_{2} O_{2}$

$(iii)$ Hydrogen peroxide is a powerful oxidant in acids as well as alkaline medium. It oxidises acidified ferrous sulphate
$2 {FeSO}_{4} + H_{2} {SO}_{4} + H_{2} O_{2} ⟶ {Fe}_{2} {({SO}_{4})}_{3} + 2 H_{2} O Ferrous Ferric sulphate sulphate$

So, here ferrous sulphate is oxidised.

$(iv)$ $N_{2} H_{4} + 2 H_{2} O_{2} \to N_{2} + 4 H_{2} O$

Here oxidation state of nitrogen in hydrazine is $- 2$ and oxidation state of nitrogen in $N_{2}$ is $0$ . So it is oxidised.

$(v)$ $H_{2} O_{2} $ oxidises $H_{2} S$ to $S$ .
The reaction is:
$H_{2} O_{2} + H_{2} S \to 2 H_{2} O + S$

Here in hydrogen sulphide sulphur has $- 2$ oxidation state to sulphur which has $0$ oxidation state.

So it is oxidised

$(vi)$ Lead sulphide $PbS$ reacts with hydrogen peroxide, $H_{2} O_{2}$ to give lead sulphate ${PbSO}_{4}$ and water as products. The balanced is
$PbS + 4 H_{2} O_{2} \to {PbSO}_{4} + 4 H_{2} O$

This is a redox reaction in which hydrogen peroxide oxidises lead sulphide in which sulphur is in $- 2$ oxidation state to lead sulphate in which sulphur is in $+ 6$ oxidation state. On the other hand, oxygen of hydrogen peroxide in $- 1$ state is reduced to $- 2$ state in water. So, it can be oxidised.

$(vii)$ Ozone is stronger oxidizing agents than $H_{2} O_{2}$ .

Because Ozone highly unstable and hence it dissociates to form $O_{2} $ molecule and nascent oxygen which is extremely highly unstable and hence it reacts quickly to oxidise anything in order to attain stability by reducing itself.

Whereas $H_{2} O_{2}$ is a stable enough molecule compared to $O_{3}$ and hence not strong enough to act as a strong enough oxidizing agent.

$H_{2} O_{2}$ reduces $O_{3}$ to $O_{2}$

$O_{3} + H_{2} O_{2} \to H_{2} O + 2 O_{2}$

So, i, iv, v and vi are correct

How many compound(s) or ion(s) can be oxidised by $H_{2} O_{2}$ among the following:

$(i)$ ${AsO}_{3}^{3 -}$

$(ii)$ ${SO}_{4}^{2 -}$

$(iii)$ ${Fe}_{2} {({SO}_{4})}_{3}$

$(iv)$ ${NH}_{2} - {NH}_{2}$

$(v)$ $H_{2} S$

$(vi)$ $PbS$

$(vii)$ $O_{3}$

Important Questions on The p-Block Elements

Learn and Prepare for any exam you want !

How many compound(s) or ion(s) can be oxidised by H2O2 among the following: i AsO33- ii SO42- iii Fe2SO43 iv NH2-NH2 v H2S vi PbS vii O3

Important Questions on The p-Block Elements

Learn and Prepare for any exam you want !

How many compound(s) or ion(s) can be oxidised by $H_{2} O_{2}$ among the following:

$(i)$ ${AsO}_{3}^{3 -}$

$(ii)$ ${SO}_{4}^{2 -}$

$(iii)$ ${Fe}_{2} {({SO}_{4})}_{3}$

$(iv)$ ${NH}_{2} - {NH}_{2}$

$(v)$ $H_{2} S$

$(vi)$ $PbS$

$(vii)$ $O_{3}$