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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