Recording Significant Figures in Measurements

The video tutorial explains how to determine the number of significant figures in measurements using lab equipment. It emphasizes recording known digits with certainty and adding one uncertain digit. The tutorial provides examples using a graduated cylinder and a ruler, illustrating how to read measurements and estimate the last digit based on the smallest scale increments.

What is the rule for recording significant figures in a measurement?

• Record only the digits that are not certain.

• Record only the uncertain digit.

• Record all digits that are known with certainty plus one uncertain digit.

• Record all digits that are known with certainty.

In the measurement 2.2405 grams, which digit is uncertain?

• 5

• 4

• 2

• 0

When reading a graduated cylinder, what should you do if the meniscus falls between two tick marks?

• Ignore the measurement.

• Record the higher tick mark only.

• Estimate the value between the two tick marks.

• Record the lower tick mark only.

If the meniscus of water in a graduated cylinder falls between 52 mL and 53 mL, what is the correct way to record the measurement?

• 52 mL

• 53 mL

• 52.5 mL

• 52.x mL, where x is an estimated digit

Why might different people record slightly different measurements for the same volume in a graduated cylinder?

• Because they use different equipment.

• Because they estimate the uncertain digit differently.

• Because they read the scale incorrectly.

• Because the water level changes.

In the example of the graduated cylinder with 17 mL, what is the estimated digit if the measurement is recorded as 17.5 mL?

• 1

• 5

• 0

• 7

What is the smallest graduation on a scale if the tick marks represent 1 mL?

• 0.1 mL

• 1 mL

• 10 mL

• 0.01 mL

When measuring the length of a bar with a ruler, what should you do if the length falls between two tick marks?

• Record the higher tick mark only.

• Ignore the measurement.

• Record the lower tick mark only.

• Estimate the value between the two tick marks.

If a ruler shows a length of 3.2 cm, what is the estimated digit if the measurement is recorded as 3.24 cm?

• 2

• 4

• 3

• 1

How many significant figures are in the measurement 3.24 cm?

• 4

• 3

• 2

• 1