To solve the question you use the following formula:
concentration (1) × volume (1) = concentration (1) × volume (1)
3 M × volume (1) = 1.8 M × 50 mL
volume (1) = (1.8 M × 50 mL) / 3 M = 30 mL
Answer:
30.0 ml
Explanation:
1.8 M means 1.8 moles of HCl in 1 liter (or 1000 ml) of solution.
50 ml of solution has:
1.8 moles/(x moles) = 1000 ml/(50 ml)
x = 1.8 moles/(1000 ml) * 50 ml = 0.09 moles
3 M means 3 moles of HCl in 1 liter of solution.
0.09 moles are found in:
3 moles/(0.09 moles) = 1000 ml/(x ml)
x = 0.09 moles * 1000 ml/(3 moles) = 30 ml
Then, you have to take a sample of 30 ml of a solution 3 M and add 20 ml of the solvent (probably water) to make 50 ml of solution 1.8 M of HCl.
