How many milliliter of conc. HNO3 would be necessary to prepare 500ml of 20% of HNO3 solution?

3 answers

First calculate the percent HNO3 in conc HNO3. Do you have the percent? Most concn HNO3 is 68% by weight HNO3.
Then
500 mL x 0.20 = ?mL x 0.68.
Conc hno3 is not given.
You MUST know how strong it is in the bottle; else you don't have enough info. Concd HNO3 sold commercially is 68-70% by weight. It says that on the bottle. That's why I gave you the number in my response.