Midterm 1 Q!C

[Natalie_Martinez_1I]

Potassiumpermanganate,KMnO4,isaninorganicchemicalcompoundusedfor cleaning wounds. 5.00 g of KMnO4 is dissolved in a 150.00 mL flask of water.
If 20.00 mL of this solution is removed and placed in a new 2nd 250.00 mL flask and
filled with water, what is the concentration of the solution in the 2nd flask?
Molar Masses: K (39.10 g/mol) Mn (54.94 g/mol) O (16.00 g/mol)
16.00 x 4 = 64 64.00 + 54.94 + 39.10 = 158.04 g/mol of KMnO4
5.00 g/158.04 g/mol = 0.0316375 mol
0.0316375 mol/ 0.150 L = 0.210917 mol/L
20.00 ml/250.00 ml x 0.210917 mol/L = 0.016873 mol.L-1 or 1.69 x 10-2 mol.L-1

Can someone explain why you had to divide 20ml by 250ml to get the molarity in this question please?

[AnnaYan_1l]

What I did to solve this problem was:







Hope that clarifies the process more!

[Natalie_Martinez_1I]

It does thank you so much!