Answer:
5mL of 6 M HCl is needed to make 100 mL of 0.3 M of HCl.
Step-by-step explanation:
Using the dilution formula:
M1V1 = M2V2
M1 = 0.30 M
V1 = 100 mL
M2 = 6.0 M
V2 = unknown
Re-arranging the formula by making V2 the subject of the equation:
V2 = M1V1 / M2
V2 = 0.30 * 100 / 6
V2 = 5 mL
The volume of 6 M of HCl needed to make 0.3 M at 100 mL is 5 mL.