`KMnO_4` reacts with `Na_2S_2O_3` in acidic, strongly basic and aqueous (neutral) media. `100mL` of `LMnO_4` reacts with 100 mL of 0.1 M `Na_2S_2O_3` in acidic, basic and neutral media.
Q. The molality (m) of `KMnO_4` in the acidic medium is (Density of `KMnO_4`) solution `=1.58^(-1)` `Mw(KMnO_4)=158gmol^(-1))`

Options

A. `0.025`
B. `0.25`
C. `0.12`
D. `0.012`

Answer

d

Explanation

`d_(sol)=M((Mw_2)/(1000)+(1)/(m))`
`M=0.02`
`1.58=0.02((158)/(1000)+(1)/(m))`
solve for m: `m=0.012`