Answer:
1) If the hydrogen ion concentration of a solution is 10–10M, is the solution is definitely  alkaline. The thing I used to determine that fact is basic point  - pH above 7 is always alkaine, and as a proof we can see from the task that the concentration of hydroxyl OH- is pretty higher than hydrogen H+, which is a direct charachteristic of alkain solution.
Explanation:Here is a tip for you, I bet it will be useful :
>7 = basic
<7 = acidic
7 = neutral
