Question

To calculate molarity and strength of kmno4 solution by titrating it against m/20 mohr's salt solution

Answer 1

The reaction between KMnO4 and mohr's salt is redox reaction where KMnO4 act as oxidizing agent which oxidizes it as Fe+2 to Fe+3 ions in acidic medium . The indicator gives the light pink color at the end of reaction.

the molarity  can be calculates by using data following:

Volume of mohr's salt pipette out 20ml

Molarity of mohr's salt solution = 0.05M

Calculation :

(M1V1)N1 =( M2V2) N2

M1 = molarity of mohr's solution = 0.05M

V1 = volume of mohr's salt sollution = 20ml

N1 = no. of moles of mohr's salt solution = 10

M2 = molarity of KMnO4= M2

V2 = volume of KMnO4 = 19 ml

N2 = no. of moles of KMnO4 = 2

The strength of KMMnO4 in gm/L

molarity *mol. mass

M2 * 158= 0.0105 * 158 =1.66gm/L

where M2 = 0.0105M

So

the molarity of given by KMnO4 = 0.01M

the strength of given KMnO4 solution = 1.58gm/L

V1 =