Question

Measurement and Accuracy

Procedure

Obtain 5 large test tubes (all the same size), a test tube rack, 3 beakers of colored water A-C, and 3 graduated cylinders.

With a Sharpie, label the tubes 1-5

Measure 25 mL of solution from beaker A (red) using a clean graduated cylinder. Pour into tube 1.

Measure 28 mL of solution from beaker B (yellow) using a clean graduated cylinder. Pour into tube 3.

Measure 22 mL of solution from beaker C (blue) using a clean graduated cylinder. Pour into tube 5.

Pour 8 mL of solution from tube 3 into a clean graduated cylinder and add it into tube 4.

Pour 7 mL of solution from tube 5 into a clean graduated cylinder and add it into tube 4. Mix the solution by swirling the tube.

Pour 10 mL of solution from tube 1 into a clean graduated cylinder and add it into tube 2.

Pour 5 mL of solution from tube 3 into a clean graduated cylinder and add it into tube 2. Mix the solution by swirling the tube.

Data Sheet

Test tube	Color observed	Volume contained in tube at the end
1
2
3
4
5

For the column above labeled “Volume contained in the tube at the end”, calculate the volume that each solution should contain. After completing your calculations, do your test tubes appear to match your math?

If not, give an explanation of why they would be different.

Compare your tube 2 with two other groups’ tube 2, are they the exact same shade of color?

If not, give an explanation of why they would be different.

If the colors are different, which group has the “right” color? How did you determine this?

Answer 1

Test tube	colour observed	volume in the tube at the end
1.	Red	15mL
2.	orange	15mL
3.	yellow	15mL
4.	green	15mL
5.	blue	15mL

While transferring liquid from beakers to graduated cylinders and from cylinders to test
tubes certain tiny volumes of liquid is not delivered properly resulting in a mismatch
of values.
Lack of precision in the delivery of volumes causes this different shades when you compare.
Now, if the measured volume and original values match then you can say that particular
group has the right colour.