What is the volume in the graduated cylinder?

The cylinder contains 76.0 mL.


Step 1: Determine the scale increment

To find the scale increment, subtract the values of any two adjacent labeled graduations and divide by the number of intervals between them. In the graduated cylinder above, first subtract 80 mL - 70 mL = 10 mL. Next, count that there are ten intervals between the labeled graduations. Therefore, the scale increment is 10 mL/10 graduations = 1 mL/graduation.

Step 2: Use the graduations to find all certain digits

Use the labeled graduations and the scale increment to find the certain digits in the measurement. The first digit is 7, since the last labeled graduation below the meniscus is 70. Next, use the scale increment. There are six unlabeled graduations below the meniscus, and each graduation represents 1 mL, for an additional 6 mL. Therefore, the certain digits of the reading are 76 mL.

Step 3: Estimate the uncertain digit and obtain a reading

Estimate the distance that the meniscus lies between the two graduations as a decimal fraction and multiply by the scale increment. Above, the meniscus is lying on the graduation, so the final digit in the reading is (0.0 increment) * (0.1 mL/increment) = 0.0 mL. The uncertain reading is added to the certain digits, so the volume measurement is 76.0 mL.



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