Unit 2 Scientific Measurement Review

The diameter of a carbon atom is 0.000 000 000 154 m. What is this number expressed in scientific notation?

• 1.54 x 10¹² m
• 1.54 x 10^-12 m
• 1.54 x 10¹⁰ m
• 1.54 x 10^-10 m

The expression of 5008 km in scientific notation is ____.

• 5.008 x 10³ km
• 50.08 X 10^-4 km
• 5.008 x 10^-3 km
• 5.008 x 10⁴ km

The closeness of a measurement to its true value is a measure of its ___.

• precision
• accuracy
• reproducibility
• usefulness

Which of the following measurements contains two significant figures?

• 0.004 00 L
• 0.004 04 L
• 0.000 44 L
• 0.004 40 L

Which group of measurements is the most precise? (Each group of measurements is for a different object.)

• 2 g, 3 g, 4 g
• 2.0 g, 3.0 g, 4.0 g
• 2 g, 2.5 g, 3 g
• 1 g, 3 g, 5 g

Three different people weigh a standard mass of 2.00 g on the same balance.  Each person obtains a reading of 7.32 g for the mass of the standard.  These results imply that the balance that was used is ____.

• accurate
• precise
• accurate and precise
• neither accurate nor precise

Which of the following measurements is expressed to three significant figures?

• 0.007 m
• 7077 mg
• 7.30 x 10^-7 km
• 0.070 mm

In the measurement 0.503 L, which digit is the estimated digit?

• 5
• the 0 immediately to the left of the 3
• 3
• the 0 to the left of the decimal point

How many significant figures are in the measurement 40,500 mg?

• two
• three
• four
• five

What is the measurement 111.009 mm rounded off to four significant digits?

• 111 mm
• 111.0 mm
• 111.01 mm
• 110 mm