Q: A patient receives 250 mg of a medication. The doctor wants to know how many grams this is. Which of the following is the correct conversion?

$$250 \ \text{mg} \times \frac{1 \ \text{g}}{1000 \ \text{mg}} = 0.25 \ \text{g}$$

Q: Which of the following statements about density is correct?

Density is calculated as $$\text{Density} = \frac{\text{mass}}{\text{volume}}.$$

Q: A sample of ethanol has a density of $$0.789 \ \text{g/mL}. $$What is the mass of $$50.0 \ \text{mL} of $$ethanol?

$$0.789 \ \text{g/mL} \times 50.0 \ \text{mL} = 39.5 \ \text{g}$$

Q: How much heat (in joules) is required to raise the temperature of $$25.0 \ \text{g} of $$water from $$20.0^\circ \text{C} to$$ $$50.0^\circ \text{C}$$? (Specific heat of water $$= 4.18 \ \text{J/g}^\circ \text{C})$$

$$q = m \cdot c \cdot \Delta T = 25.0 \ \text{g} \times 4.18 \ \text{J/g}^\circ \text{C} \times (50.0 - 20.0)^\circ \text{C} = 3,135 \ \text{J}$$

Q: A sample of gold has a mass of $$96.5 \ \text{g}$$ and a volume of $$5.00 \ \text{cm}^3. $$What is the density of sopld?

$$\text{Density} = \frac{96.5 \ \text{g}}{5.00 \ \text{cm}^3} = 19.3 \ \text{g/cm}^3$$

Q: A nurse needs to convert a patient's temperature from $$39.0^\circ \text{C} to $$Fahrenheit. Which formula should be used?

$$^\circ \text{F} = (^\circ \text{C} \times \frac{9}{5}) + 32$$

Q: Which of the following is a correct equality?

$$1 \ \text{cm}^3 = 1 \ \text{mL}$$

Question 1

A patient receives 250 mg of a medication. The doctor wants to know how many grams this is. Which of the following is the correct conversion?

Accepted Answer

$$250 \ 	ext{mg} 	imes \frac{1 \ 	ext{g}}{1000 \ 	ext{mg}} = 0.25 \ 	ext{g}$$

Question 2

Which of the following statements about density is correct?

Accepted Answer

Density is calculated as $$	ext{Density} = \frac{	ext{mass}}{	ext{volume}}.$$

Question 3

A sample of ethanol has a density of $$0.789 \ 	ext{g/mL}. $$What is the mass of $$50.0 \ 	ext{mL} of $$ethanol?

Accepted Answer

$$0.789 \ 	ext{g/mL} 	imes 50.0 \ 	ext{mL} = 39.5 \ 	ext{g}$$

Question 4

Which of the following is an example of a chemical change?

Accepted Answer

Iron rusting in moist air

Question 5

A heating curve shows a flat line at $$100^\circ 	ext{C}$$ for water. What process is occurring at this plateau?

Accepted Answer

Boiling (liquid to gas)

Question 6

How much heat (in joules) is required to raise the temperature of $$25.0 \ 	ext{g} of $$water from $$20.0^\circ 	ext{C} to$$ $$50.0^\circ 	ext{C}$$? (Specific heat of water $$= 4.18 \ 	ext{J/g}^\circ 	ext{C})$$

Accepted Answer

$$q = m \cdot c \cdot \Delta T = 25.0 \ 	ext{g} 	imes 4.18 \ 	ext{J/g}^\circ 	ext{C} 	imes (50.0 - 20.0)^\circ 	ext{C} = 3,135 \ 	ext{J}$$

Question 7

Which of the following best describes a mixture?

Accepted Answer

A combination of two or more substances that can be separated by physical means

Question 8

Which of the following is the correct electron configuration for a neutral sodium atom ($$Z=11$$)?

Accepted Answer

$$1s^2$$\ $$2s^2$$\ $$2p^6$$\ $$3s^1$$

Question 9

Which element is a metalloid?

Accepted Answer

Silicon (Si)

Question 10

Which of the following trends is correct as you move from left to right across a period in the periodic table?

Accepted Answer

Ionization energy increases

Question 11

A sample of gold has a mass of $$96.5 \ 	ext{g}$$ and a volume of $$5.00 \ 	ext{cm}^3. $$What is the density of sopld?

Accepted Answer

$$	ext{Density} = \frac{96.5 \ 	ext{g}}{5.00 \ 	ext{cm}^3} = 19.3 \ 	ext{g/cm}^3$$

Question 12

Which of the following is an exact number?

Accepted Answer

There are 12 eggs in a dozen.

Question 13

Which of the following is the correct Lewis symbol for magnesium (Mg)?

Accepted Answer

Mg with two dots

Question 14

A nurse needs to convert a patient's temperature from $$39.0^\circ 	ext{C} to $$Fahrenheit. Which formula should be used?

Accepted Answer

$$^\circ 	ext{F} = (^\circ 	ext{C} 	imes \frac{9}{5}) + 32$$

Question 15

Which of the following is the correct number of significant figures in the measurement 0.004560?

Accepted Answer

4

Question 16

Which of the following statements about specific heat is correct?

Accepted Answer

Specific heat is the amount of heat required to raise the temperature of 1 g of a substance by $$1^\circ 	ext{C}.$$

Question 17

Which of the following is a correct equality?

Accepted Answer

$$1 \ 	ext{cm}^3 = 1 \ 	ext{mL}$$

Question 18

Which group in the periodic table contains the noble gases?

Accepted Answer

Group 18

Question 19

A block of ice at $$0^\circ 	ext{C}$$ absorbs $$334 \ 	ext{J} of $$heat and melts completely. What is the mass of the ice? (Heat of fusion for water $$= 334 \ 	ext{J/g})$$

Accepted Answer

$$m = \frac{q}{\Delta H_{fus}} = \frac{334 \ 	ext{J}}{334 \ 	ext{J/g}} = 1.00 \ 	ext{g}$$

Question 20

Which of the following best explains why steam burns are more severe than boiling water burns at the same temperature?

Accepted Answer

Steam releases additional heat of vaporization when it condenses on the skin.

Study Guide: Chemistry and Measurements, Matter and Energy, Atoms and Elements (Chapters 2–4)

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