Practice - measurements

In the sum of 54.34 + 45.66 +3.3, the number of significant figures is

• 2
• 3
• 4
• 5
• 6

Which of the following values represents the shortest distance?

• 0.000034 km
• 5.6 x 10^7 micrometer
• 200 cm
• 0.0024 m

Quantities of items that can be counted are considered exact, containing no uncertain digits. Which of the following is an exact quantity?

• 100 km
• 25 deg C
• 1 X 10^24 atoms
• 37 Liters

Which set of measurements best represents accuracy if the true value is 6.80 kg?

• 6.10 kg, 5.99 kg and 6.11 kg
• 6.65 kg, 6.80 kg and 6.95 kg
• 6.80 kg, 6.70 kg and 6.90 kg
• 5.80 kg, 6.80 kg and 7.80 kg

If the speed limit on a highway is 65 mph (miles per hour), what is the speed limit in meters per second? 1 hour = 60 minutes, 1 minute = 60 seconds, 1 mile = 1609 meters SHOW YOUR WORK

A chemistry student is experimentally determining the boiling point of a substance. The experimental boiling points (in degree Celsius) are listed below. Which one should he discard so that he can say his data is precise?

• 38.8
• 39.0
• 37.1
• 39.1
• 38.7

The number 600,000 expressed in scientific notation is

• 6.0 x 10^5
• 6.0 x 10^-5
• 60 x 10^4
• 6 x 10^5

Write the number 0.9950 in scientific notation.

(a)  

Round to one decimal place: 7.555

Cobalt has a density of 8.92 g∙cm−3. A ball of cobalt with a mass of 10.3 g, is immersed into a measuring cylinder with 15.00 mL of water. What will be be final reading of water layer in the measuring cylinder in mL? Show your work.