Answer: The correct answer for the blank is-
pH of 7.
There can be primarily three types of aqueous solution depending upon the pH value ( which represents the acidity or basicity of the solution). A pH scale ranges from 1 to 14.
The pH value 7 relates to neutral solution, above 7 is for basic solutions and below 7 shows solution is acidic.
Neutral solution means the hydrogen ion concentration is equal to the concentration of hydroxide ions.
Example of neutral solution- Water