Answer:
0.2 ml
Step-by-step explanation:
Stock dilution is done by using the formula C1V1 = C2V2 where,
C1V1 = Start volume and concentration
C2V2 = Final volume and concentration
Here,
C1V1 = C2V2
5 mg/ml * V1 = 0.1 mg/ml * 10 ml
V1 = ( 0.1 * 10 ) / 5 ml
= 1/5 ml
= 0.2 ml
So 0.2 ml of nitroglycerin stock is needed to make the final solution.