Q: A sample of mercury has a density of $$13.6 \ \mathrm{g/cm^3$}. $$What is the mass, in grams, of $$95.0 \ \mathrm{mL} of $$mercury? (Assume $$1 \ \mathrm{mL} = 1 \ \mathrm{cm^3$})$$

$$1.29 \times 10^3$ \ \mathrm{g}$$

Q: A student multiplies $$6.0 \ \mathrm{cm} by$$ $$4.00 \ \mathrm{cm}$$ and gets $$24.00 \ \mathrm{cm^2$}. $$How should the answer be reported with the correct number of significant figures?

$$2.4 \times 10^1$ \ \mathrm{cm^2$}$$

Q: A field of $$145$$ acres requires $$5.50 \ \mathrm{g/m^2$} of a $$soil supplement. How many grams are required? ($$1 \ \mathrm{km^2$} = 247$$ acres, $$1 \ \mathrm{km^2$} = 10^6$ \ \mathrm{m^2$})$$

$$3.23 \times 10^6$ \ \mathrm{g}$$

Question 1

Which of the following is an example of a quantitative observation?

Accepted Answer

The temperature increased by $$5.0 \, ^\circ \mathrm{C}.$$

Question 2

A student measures the mass of a sample three times and gets values of $$2.51 \ \mathrm{g}$$, $$2.50 \ \mathrm{g}$$, and $$2.52 \ \mathrm{g}. $$The true mass is $$2.00 \ \mathrm{g}. $$Which statement best describes the measurements?

Accepted Answer

The measurements are precise but not accurate.

Question 3

Which of the following numbers has three significant figures?

Accepted Answer

$$0.0600$$

Question 4

Convert $$25.0 \, ^\circ \mathrm{C} to $$Kelvin.

Accepted Answer

$$298.15 \, \mathrm{K}$$

Question 5

A graduated cylinder has markings every $$0.1 \ \mathrm{mL}. If $$the meniscus is between $$4.5$$ and $$4.6 \ \mathrm{mL}$$, what is the correct way to record the volume?

Accepted Answer

$$4.56 \ \mathrm{mL}$$

Question 6

Which of the following is an exact number?

Accepted Answer

$$1 \ \mathrm{inch} = 2.54 \ \mathrm{cm}$$

Question 7

A sample of mercury has a density of $$13.6 \ \mathrm{g/cm^3$}. $$What is the mass, in grams, of $$95.0 \ \mathrm{mL} of $$mercury? (Assume $$1 \ \mathrm{mL} = 1 \ \mathrm{cm^3$})$$

Accepted Answer

$$1.29 	imes 10^3$ \ \mathrm{g}$$

Question 8

Which of the following best describes an endothermic process?

Accepted Answer

Heat flows from the surroundings to the system and the temperature of the surroundings decreases.

Question 9

A student multiplies $$6.0 \ \mathrm{cm} by$$ $$4.00 \ \mathrm{cm}$$ and gets $$24.00 \ \mathrm{cm^2$}. $$How should the answer be reported with the correct number of significant figures?

Accepted Answer

$$2.4 	imes 10^1$ \ \mathrm{cm^2$}$$

Question 10

Which of the following is the correct equation to convert Celsius to Fahrenheit?

Accepted Answer

$$^\circ \mathrm{F} = 1.8(^\circ \mathrm{C}) + 32$$

Question 11

A $$22 \ \mathrm{mg}$$ sample of gasoline has a density of $$0.754 \ \mathrm{g/cm^3$}. $$What is its volume in $$\mathrm{mL}$$? (1 g = 1000 mg)

Accepted Answer

$$0.029 \ \mathrm{mL}$$

Question 12

Which of the following is NOT a base SI unit?

Accepted Answer

liter (L)

Question 13

A field of $$145$$ acres requires $$5.50 \ \mathrm{g/m^2$} of a $$soil supplement. How many grams are required? ($$1 \ \mathrm{km^2$} = 247$$ acres, $$1 \ \mathrm{km^2$} = 10^6$ \ \mathrm{m^2$})$$

Accepted Answer

$$3.23 	imes 10^6$ \ \mathrm{g}$$

Question 14

Which of the following statements about significant figures is correct?

Accepted Answer

Zeroes to the right of a decimal point and after a nonzero digit are significant.

Question 15

Which of the following is an example of a systematic (determinate) error?

Accepted Answer

A balance that always reads $$0.05 \ \mathrm{g}$$ too high.

Question 16

Which of the following is an intensive property?

Accepted Answer

Density

Question 17

A student adds $$23.46 \ \mathrm{cm}$$ and $$7.1 \ \mathrm{cm}. $$What is the correct answer with the proper number of significant figures?

Accepted Answer

$$30.6 \ \mathrm{cm}$$

Question 18

Which of the following best describes the First Law of Thermodynamics?

Accepted Answer

Energy is conserved; it can be converted from one form to another but not created or destroyed.

Question 19

Which of the following is the correct relationship for kinetic energy?

Accepted Answer

$$KE = \frac{1}{2}mv^2$

Question 20

A $$1.00 \ \mathrm{kg}$$ sample of water is heated from $$20.0 \ ^\circ \mathrm{C} to$$ $$30.0 \ ^\circ \mathrm{C}. $$How many kilocalories ($$\mathrm{kcal}) of $$energy are required? (Specific heat of water $$= 1.00 \ \mathrm{cal/g\cdot ^\circ C}$$, $$1 \ \mathrm{kcal} = 1000 \ \mathrm{cal})$$

Accepted Answer

$$10.0 \ \mathrm{kcal}$$

Essentials: Units, Measurement, and Problem Solving in General Chemistry

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