Final answer:
When hydrochloric acid (HCl) reacts with barium oxide (BaO), it forms barium chloride (BaCl2) and water (H2O). There will be no excess OH- ions in the final solution.
Step-by-step explanation:
When hydrochloric acid (HCl) reacts with barium oxide (BaO), it forms barium chloride (BaCl2) and water (H2O). The balanced chemical equation for this reaction is:
HCl + BaO -> BaCl2 + H2O
Based on the given amounts of reactants (20 mL of 0.05 M HCl and 30 mL of 0.10 M BaO), we can calculate the moles of each substance:
moles of HCl = volume (L) x concentration (mol/L)
moles of HCl = 0.020 L x 0.05 mol/L = 0.001 mol
moles of BaO = 0.030 L x 0.10 mol/L = 0.003 mol
Since the balanced equation has a 1:1 mole ratio between HCl and BaO, all of the HCl will react with the BaO. Therefore, there will be no excess OH- ions in the final solution.