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Reading Scales Module. From http://www.uwplatt.edu/chemep/chem/chemscape/labdocs/catofp/measurea/scales/scales.htm. meniscus. Curved surface of liquid in a cylindrical container. Read from the BOTTOM of the meniscus. Important Point. Read a scale at eye level. Not from an angle.
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Reading Scales Module From http://www.uwplatt.edu/chemep/chem/chemscape/labdocs/catofp/measurea/scales/scales.htm
meniscus • Curved surface of liquid in a cylindrical container. • Read from the BOTTOM of the meniscus.
Important Point • Read a scale at eye level • Not from an angle
Reading A ScaleStep One: Determine the Increment • Scale is made of graduations. Some are labeled at regular intervals, with smaller, unlabeled graduations between them.
Reading a ScaleStep One: Determine the Increment • To find the scale increment, subtract the values of any two adjacent labeled graduations and divide by the number of intervals between them.
Reading a Scale Step One: Determine the Increment • 60mL – 50mL = 10mL • Count the number of intervals between 50 and 60. • There are 10. • So 10mL divided by 10 = 1mL graduation
Practice • Pick 2 labels and subtract. • How many increments are there between those two numbers? • Divide
Practice • Subtract the 2 values. • Count the increments between them. • Divide
Practice • Subtract 7 – 6 • Count the increments. • Divide
Practice • 25 – 20 • Count increments. • Divide
Reading A ScaleStep Two: Use the graduations to find all certain digits.
What is the volume of the liquid in the graduated cylinder? 11.5 mL
What is the volume of the liquid in the graduated cylinder? • 76.0 mL
More interactive practice • practice scales • Lots more practice