What are the products obtained when potassium sulphate reacts with barium iodide in an aqueous medium?

SOLVE THE PUZZLE.

Down:
1. The point at which the indicator changes colour.
2. A solution in which $\left[{\mathrm{H}}^{+}\right]$ is less than $\left[{\mathrm{OH}}^{-}\right]$.
3. A base that reacts with water to form the hydroxide ion and the conjugate acid of the base.
4. Two substances related by the loss or gain of a single hydrogen ion.
5. A substance that can accept a pair of electrons to form a covalent bond.
6. A water molecule that gain a hydrogen ion becomes a positively charged ion.
7. A substance that can act as both an acid and a base.
8. A substance that can donate a pair of electrons to form a covalent bond.
10. A base that completely dissociates into metal ions and hydroxide ion in aqueous solution.

Across:
3. An acid that is only slightly ionised in aqueous solution.
9. A solution in which $\left[{\mathrm{H}}^{+}\right]$ is greater than $\left[{\mathrm{OH}}^{-}\right]$.
11. The negative logarithm of the hydrogen-ion concentration.
12. The process of adding a known amount of solution of known concentration to determine the concentration of another solution.
14. A reaction in which an acid and a base reacts to produce salt and water.
15. A solution in which the pH remains relatively constant when small amounts of acid or base are added.