Significant Figures and Measurements Quiz

Which of the following numbers has 4 significant figures?

• 0.0830

• 0.083

• 0832

• 0.08304

Answer explanation

The number 0.08304 has 4 significant figures. The leading zeros are not counted, but the digits 8, 3, 0, and 4 are significant. In contrast, 0.0830 has 3 significant figures, and 0.083 and 0832 have fewer or more than 4.

Perform the indicated mathematical operations and report the answer to the correct number of significant figures: (64.33 × 3.13) / 37.98

• 5.3

• 5.30

• 5.301

• 5.3020

Answer explanation

To solve (64.33 x 3.13) / 37.98, first calculate the product: 64.33 x 3.13 = 201.54. Then divide by 37.98 to get 5.303. The final answer should be reported with three significant figures, resulting in 5.30.

Which of the following is not a significant figure?

• A value from 1 to 9

• A zero between two digits with values from 1 to 9

• Zeros to the right of a significant digit when a decimal point is present

• Zeros to the left of the first significant digit

Answer explanation

Zeros to the left of the first significant digit are not considered significant figures, as they only serve as placeholders and do not affect the precision of the number.

Using the correct significant figures and units, what is the volume of the liquid in the graduated cylinder if the meniscus is at the 42.0 mL mark?

• 42.0 mL

• 41.5 mL

• 43 mL

• 42.00 mL

Answer explanation

The volume of the liquid is read at the meniscus, which is at the 42.0 mL mark. This value has three significant figures, making 42.0 mL the correct answer, as it accurately reflects the precision of the measurement.

How many significant figures are in the measurement 0.0050 kg?

• 1

• 2

• 3

• 4

Answer explanation

The measurement 0.0050 kg has 2 significant figures. The leading zeros (0.00) are not counted, but the '5' and the trailing zero after the decimal point are significant.

• 1

• 2

• 3

• 6

Answer explanation

The measurement 9.08x10^5 has three significant figures: the digits 9, 0, and 8 are all significant. The presence of the decimal point indicates that the zero is significant, making the total count three.

Round to the correct number of significant figures: 123.45 m + 6.789 m

• 130.239 m

• 130.24 m

• 130.2 m

• 130 m

Answer explanation

When adding 123.45 m and 6.789 m, the result is 130.239 m. However, we round to the least number of decimal places, which is two from 123.45 m. Thus, the final answer is 130.24 m.

Round to the correct number of significant figures: 8.45 g ÷ 3.2 mL

• 2.640625 g/mL

• 2.6 g/mL

• 2.64 g/mL

• 2.7 g/mL

Answer explanation

When dividing, the result should have the same number of significant figures as the measurement with the least significant figures. 3.2 has 2 significant figures, so the answer rounds to 2.6 g/mL.

The density of aluminum is 2.70 g/cm³. Which statement correctly describes this student’s experimental data?

Trial 1: 2.10 g/cm³
Trial 2: 3.05 g/cm³
Trial 3: 1.95 g/cm³

• Accurate but not precise

• Precise but not accurate

• Both accurate and precise

• Neither accurate nor precise

Answer explanation

The experimental data shows values (2.10, 3.05, 1.95 g/cm³) that are all far from the true density of aluminum (2.70 g/cm³) and vary widely, indicating neither accuracy nor precision.

Which of the following numbers contains only significant zeros?

• 0.00450

• 2,000.00

• 5.0700

• 0.000501

Answer explanation

The number 5.0700 contains significant zeros after the decimal point, indicating precision. In contrast, the other options have leading zeros or trailing zeros that do not count as significant.