KMnO4 solution needed to completely react with 25.0cm3 of ‌
M
4
FeSO4 in an acidic medium, we start by considering the balanced ionic equation: MnO4−+5Fe2++8H+⟶Mn2++5Fe3++4H2O From this equation, it's evident that 1 mole of KMnO4 reacts with 5 moles of FeSO4. For balancing the redox reaction, apply the molarity equation: ‌
M1V1
n1
(KMnO4)=‌
M2V2
n2
(FeSO4) Substitute the given values where: ‌M1=‌
M
8
(‌ molarity of ‌KMnO4) ‌M2=‌
M
4
(‌ molarity of ‌FeSO4) ‌V2=25cm3 ‌n1=1(‌ moles of ‌KMnO4) ‌n2=5(‌ moles of ‌FeSO4) ‌‌
‌
1
8
×V1
1
=‌
‌
1
4
×25
5
Solving the equation for V1 : ‌‌
1×V1
8
=‌
1×25
4×5
‌V1=‌
1×25×8
4×5
V1=10cm3‌‌‌ or ‌‌‌V1=10.0‌mL Hence, the volume of ‌