1. Using dilution formula M1V1=M2V2 where (0.72)(50)=(M2)(120) M2=0.3 mol/L
2. Same formula where (0.0075)(V1)=(50)(0.0025) V1=16.67 KMN04 But dilution needs water so last volume,V2 - the exist KMNO4 solution. Therefore 50-16.67=33.33 ml water
3. Find moles of KMnO4 using formula molarity (Molarity=number of moles/litre of solution) Therefore, (0.0075=x/0.5) Number of moles KMnO4,x= 3.75x10^-3moles Molecular mass of KMnO4 is 158g/mol. Mass of KMnO4 needed is (3.75x10^-3)(158) =0.5925g/590mg(few decimals places inaccurate due to the difference in significant figures) Volume of water need to add to reach amount of volume needed which is 500ml
