During a titration, the solution with the unknown concentration is called the .

Analyte.

Explanation:

Hello,

In this case, in a titration, an analyte is known as the the substance whose quantity or concentration is to be carefully determined (initially unknown) by using a titrant with a controlled volume and an accurately-known concentration which is also called a standard solution.

You can verify this by considering the attached picture.

Regards.

8 m/s because for him to get the same amount of energy as ray is putting out, bobby, who weighs half as much as ray, needs to run twice as fast.