Describe the preparation of 200 ml of 0.20 M HCL, starting with conc HCl (12.1M)

M1)(V1)=(M2)(V2)
(12.1)(V1)=(0.20M)(200mL)
V1=0.3025mL

Add 0.3025mL 12.1M HCl to a 200mL volumetric flask. Fill to etched line, mix well.

You now have 200mL of 0.20M HCl