To measure the quantity of MnCl_2 dissolved i | vedclass

Name: Exam Paper Generator | JEE NEET Paper Generator | Vedclass
Brand: Vedclass
Rating: 5 (35 reviews)

Question

(D) The reaction involves the conversion of $Mn^{2+}$ to $MnO_4^-$ and then the titration of $MnO_4^-$ with oxalic acid $(H_2C_2O_4)$.Step $1$: Oxidat

Vedclass · Accepted Answer

$126$

Vedclass · Answer

(D) The reaction involves the conversion of $Mn^{2+}$ to $MnO_4^-$ and then the titration of $MnO_4^-$ with oxalic acid $(H_2C_2O_4)$.Step $1$: Oxidation of $Mn^{2+}$ to $MnO_4^-$. The change in oxidation state of $Mn$ is from $+2$ to $+7$,so the n-factor is $5$.Step $2$: Reduction of $MnO_4^-$ by $H_2C_2O_4$. The change in oxidation state of $Mn$ is from $+7$ to $+2$ (n-factor $= 5$),and for $H_2C_2O_4$ to $CO_2$,the change in oxidation state of $C$ is from $+3$ to $+4$ (n-factor $= 2$ per molecule).By the law of equivalence,the number of equivalents of $MnCl_2$ equals the number of equivalents of $H_2C_2O_4$.$n_{MnCl_2} 	imes 5 = n_{H_2C_2O_4} 	imes 2$$\frac{w}{M_{MnCl_2}} 	imes 5 = \frac{225 \ mg}{90 \ g \ mol^{-1}} 	imes 2$Given $M_{MnCl_2} = 55 + 2 	imes 35.5 = 126 \ g \ mol^{-1}$.$\frac{w}{126} 	imes 5 = \frac{225}{90} 	imes 2$$\frac{w}{126} 	imes 5 = 2.5 	imes 2 = 5$$w = 126 \ mg$.

Similar Questions

Assign $A$,$B$,$C$,$D$ from the given type of reaction.
$Pb(NO_3)_2 + H_2SO_4 \longrightarrow PbSO_4 \downarrow + 2HNO_3$

$O_3 + 2KI_{(aq)} \rightarrow ?$ The product of the reaction is:

$PbO$ and $PbO_2$ react with $HCl$ according to the following chemical equations:
$(i)$ $2PbO + 4HCl \to 2PbCl_2 + 2H_2O$
$(ii)$ $PbO_2 + 4HCl \to PbCl_2 + Cl_2 + 2H_2O$
Why do these compounds differ in their reactivity?

$A_2O_x$ is oxidized to $AO_3^-$ by $MnO_4^-$ in acidic medium. If $1.5 \times 10^{-3} \text{ mole}$ of $A_2O_x$ requires $40 \text{ mL}$ of $0.03 \text{ M } KMnO_4$ solution in acidic medium,which of the following statement$(s)$ is/are correct?

By passing $H_2S$ gas in acidified $KMnO_4$ solution,we get

Vedclass Test Series

Exam Paper Generator

Online Exam Module