What is the molarity of 20.00 mL of a stock solution made with 12.003 g of potassium oxalate monohydrate?
NOTE: Give your answer to 3 significant figures and do not report units with your response.
The question makes no sense to me. A stock solution is something one uses to dilute and make various desired molarities. The molarity of the stock solution is the same in 1 mL or 100 mL; it's the 20.00 mL that is confusing.
IF you placed 12.003 g K2C2O4 in the 20.00 mL, then
12.003 g/molar mass K2C2O4.H2O = moles = ??
M = ??moles/0.02000.