Answer:
6.56x10⁻³ mol
Explanation:
First we calculate how many HCl moles are there in 50.0 mL of a 0.1800 M solution:
Then we need to calculate how many HCl moles were in excess, that number is the same as the number of NaOH moles they reacted with:
Finally we calculate the difference between the original number of HCl moles and the number remaining after the reaction with XnCO₃: