Question

why does the procedure ask you to use a new graduated cylinder with each unknown solution?
you need to use all lab equipment and there are 4 graduated cylinders.
the graduated cylinder label, unknown solution label, and tube labels must match.
reusing the graduated cylinder will contaminate the unknown solutions due to residue remaining in the cylinder.

Explanation:

In laboratory - work, reusing a graduated cylinder without proper cleaning can lead to residue from previous solutions contaminating new ones, affecting the accuracy and integrity of experiments.

Answer:

Reusing the graduated cylinder will contaminate the unknown solutions due to residue remaining in the cylinder.