Answer:
0.246 M
Explanation:
The reaction that takes place is:
- Sr(OH)₂ + 2HCl → SrCl₂ + 2H₂O
First we calculate how many HCl moles reacted, using the given volume and concentration:
- 0.350 M * 21.1 mL = 7.385 mmol HCl
Then we convert HCl moles into Sr(OH)₂ moles, using the stoichiometric coefficients of the balanced reaction:
- 7.385 mmol HCl * [tex]\frac{1mmolSr(OH)_2}{2mmolHCl}[/tex] = 3.692 mmol Sr(OH)₂
Finally we calculate the concentration of the original Sr(OH)₂ solution:
- 3.692 mmol Sr(OH)₂ / 15.0 mL = 0.246 M
