Q: A sample of gasoline contains $$1.50 \times 10^2$ grams. Express this mass in kilograms using scientific notation.

$$ 1.50 \times 10$$^{-1}$$ \ \mathrm{kg} $$

Q: Which of the following is the correct relationship for density?

$$ d = \frac{\text{mass}}{\text{volume}} $$

Q: A runner burns $$500 \ \mathrm{Cal}$$ during a workout. How many joules is this? ($$1 \ \mathrm{cal} = 4.184 \ \mathrm{J}$$, $$1 \ \mathrm{Cal} = 1000 \ \mathrm{cal})$$

$$ 2.09 \times 10^6$ \ \mathrm{J} $$

Question 1

Which of the following is the correct SI base unit for measuring temperature?

Accepted Answer

Kelvin (K)

Question 2

A student measures the mass of a block three times and records 8.21 g, 8.22 g, and 8.20 g. The true mass is 10.00 g. Which statement best describes the student's measurements?

Accepted Answer

The measurements are precise but not accurate.

Question 3

Which of the following numbers has three significant figures?

Accepted Answer

0.00340

Question 4

Convert 25.0 °C to Kelvin. Use the correct number of significant figures.

Accepted Answer

$$ 298 \ \mathrm{K} $$

Question 5

A cube of metal has an edge length of $$2.00 \ \mathrm{cm}$$ and a mass of $$32.0 \ \mathrm{g}. $$What is its density in $$\mathrm{g/cm^3$}$$?

Accepted Answer

$$ 4.00 \ \mathrm{g/cm^3$} $$

Question 6

Which of the following is an example of an exact number?

Accepted Answer

There are 12 eggs in a dozen

Question 7

A sample of gasoline contains $$1.50 	imes 10^2$ grams. Express this mass in kilograms using scientific notation.

Accepted Answer

$$ 1.50 	imes 10$$^{-1}$$ \ \mathrm{kg} $$

Question 8

Which of the following best describes the law of conservation of energy?

Accepted Answer

Energy is neither created nor destroyed, only transformed.

Question 9

A reaction absorbs $$150 \ \mathrm{J} of $$heat from the surroundings. How is this process classified?

Accepted Answer

Endothermic, $$\Delta E is $$positive

Question 10

Which of the following conversion factors is correct for converting inches to centimeters?

Accepted Answer

$$ \frac{2.54 \ \mathrm{cm}}{1 \ \mathrm{in}} $$

Question 11

A student adds $$12.11 \ \mathrm{g}$$ and $$0.023 \ \mathrm{g}. $$What is the correct answer with the proper number of significant figures?

Accepted Answer

$$ 12.13 \ \mathrm{g} $$

Question 12

Which of the following is the correct relationship for density?

Accepted Answer

$$ d = \frac{	ext{mass}}{	ext{volume}} $$

Question 13

A $$250.0 \ \mathrm{mL}$$ sample of ethanol has a density of $$0.789 \ \mathrm{g/mL}. $$What is its mass in grams?

Accepted Answer

$$ 197 \ \mathrm{g} $$

Question 14

Which of the following is NOT a base SI unit?

Accepted Answer

Gram (g)

Question 15

A measurement is recorded as $$0.00450 \ \mathrm{g}. $$How many significant figures does it have?

Accepted Answer

3

Question 16

Which of the following best describes a systematic error?

Accepted Answer

An error that is always too high or too low in the same direction

Question 17

A $$1.00 \ \mathrm{L}$$ sample of water has a mass of $$1.00 \ \mathrm{kg}. $$What is the density of water in $$\mathrm{g/cm^3$}$$?

Accepted Answer

$$ 1.00 \ \mathrm{g/cm^3$} $$

Question 18

A runner burns $$500 \ \mathrm{Cal}$$ during a workout. How many joules is this? ($$1 \ \mathrm{cal} = 4.184 \ \mathrm{J}$$, $$1 \ \mathrm{Cal} = 1000 \ \mathrm{cal})$$

Accepted Answer

$$ 2.09 	imes 10^6$ \ \mathrm{J} $$

Question 19

Which of the following is the correct way to round $$48,457 g to $$two significant digits?

Accepted Answer

$$ 48,000 \ \mathrm{g} $$

Measurement, Problem Solving, and the Mole Concept: Essentials for General Chemistry

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