Question : State whether the following are true or false.
SO2 gas changes the colour of a KMnO4(aq) solution
They have taken this as false and given the following equation:
SO2+H2O+2KMnO4-->K2SO4+MnSO4+H2SO4 (not balanced)
But why they have taken this as false when Mn2+ created here is colourless (Does K2SO4 has a colour?)
When the medium is acidic,the colour of the solution does change from purple(MnO4^- is purple and SO2 is colourless) to colourless (Mn^2+) right?
And they haven't given whether the medium is acidic/basic,too.
[From what I've learned this reaction takes place in acidic medium(MnO4^- -->Mn^2+) ]
And I've learned that in basic medium they react as follows;
MnO4^- + SO2+4OH^- -->MnO2+SO4^2- + H2O (not balanced)
And in this case the colour of the solution should change from purple(MnO4^-) to brown/black (MnO2)
So,to my knowledge, in these both cases,the colour of the solution does change.
So I don't understand why they've taken the above statement as false.
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