36.5k views
2 votes
A student mixes four reagents together, thinking that the solutions will neutralize each other. The solutions mixed together are 50.0 ml of 0.100 m hydrochloric acid, 100.0 ml of 0.200 m of nitric acid, 500.0 ml of 0.0100 m calcium hydroxide, and 200.0 ml of 0.100 m rubidium hydroxide. Is the resulting solution neutral?

User Iambdot
by
8.4k points

1 Answer

2 votes

Final answer:

After calculating the total moles of H+ and OH- ions, it becomes apparent that the solution would have more OH- ions than H+ ions, owing to calcium hydroxide providing two OH- ions per molecule. Hence, the resulting solution is basic and not neutral.

Step-by-step explanation:

To determine if the resulting solution is neutral, we need to calculate the total moles of H+ ions and OH- ions in the mixed solutions. For acids: 50.0 ml of 0.100 M HCl provides 5.00 mmol of H+, and 100.0 ml of 0.200 M HNO3 provides 20.00 mmol of H+, totaling 25.00 mmol of H+. For bases: 500.0 ml of 0.0100 M Ca(OH)2 provides 5.00 mmol of OH-, and 200.0 ml of 0.100 M RbOH provides 20.00 mmol of OH-, also totaling 25.00 mmol of OH-. Since the total moles of H+ and OH- are equal, in theory, the solution should be neutral if all react completely. However, the capacity of OH- from Ca(OH)2 should be doubled as it provides two OH- per molecule, meaning the actual moles of OH- provided by Ca(OH)2 would be 10.00 mmol. This makes the total OH- 30.00 mmol, which surpasses the moles of H+, indicating the resulting solution is basic, not neutral.