$$\frac{0.250\ \mathrm{g}}{50\ \mathrm{mg}} \times \frac{1000\ \mathrm{mg}}{1\ \mathrm{g}} = 5$$ tablets

$$^\circ\mathrm{C} = (98.6 - 32) \times \frac{5}{9} = 37.0^\circ\mathrm{C}$$

$$\frac{0.50\ \mathrm{g}}{100\ \mathrm{mL}} \times 100\% = 0.50\%$$

Question 1

Which of the following best describes a homogeneous mixture?

Accepted Answer

A mixture in which the composition is uniform throughout, such as salt dissolved in water.

Question 2

Which of the following statements about elements in the same group (family) of the periodic table is correct?

Accepted Answer

They have similar chemical properties because they have the same number of valence electrons.

Question 3

A patient is prescribed 0.250 g of a medication. The available tablets contain 50 mg each. How many tablets should the patient take?

Accepted Answer

$$\frac{0.250\ \mathrm{g}}{50\ \mathrm{mg}} 	imes \frac{1000\ \mathrm{mg}}{1\ \mathrm{g}} = 5$$ tablets

Question 4

Which of the following is the correct molecular formula for a molecule containing 2 hydrogen atoms and 1 oxygen atom?

Accepted Answer

$$\mathrm{H}_2\mathrm{O}$$

Question 5

A sample of metal has a mass of 45.0 g and a volume of 15.0 mL. What is its density?

Accepted Answer

$$\mathrm{Density} = \frac{45.0\ \mathrm{g}}{15.0\ \mathrm{mL}} = 3.0\ \mathrm{g/mL}$$

Question 6

Which of the following best explains why water has a high specific heat capacity?

Accepted Answer

Water molecules form hydrogen bonds, which require more energy to increase their temperature.

Question 7

Convert a temperature of 98.6 $$^\circF ($$normal human body temperature) to degrees Celsius.

Accepted Answer

$$^\circ\mathrm{C} = (98.6 - 32) 	imes \frac{5}{9} = 37.0^\circ\mathrm{C}$$

Question 8

Which of the following is a physical change?

Accepted Answer

Ice melting to form liquid water.

Question 9

A solution contains 0.50 g of active ingredient in 100 mL. What is the percent (w/v) concentration of the active ingredient?

Accepted Answer

$$\frac{0.50\ \mathrm{g}}{100\ \mathrm{mL}} 	imes 100\% = 0.50\%$$

Question 10

Which of the following statements about specific gravity is correct?

Accepted Answer

Specific gravity is the ratio of the density of a substance to the density of water.

Question 11

A chemical equation is balanced when:

Accepted Answer

The number of atoms of each element is the same on both sides of the equation.

Question 12

Which of the following is the correct conversion factor to convert 5.0 kg to grams?

Accepted Answer

$$5.0\ \mathrm{kg} 	imes \frac{1000\ \mathrm{g}}{1\ \mathrm{kg}} = 5000\ \mathrm{g}$$

Question 13

Which of the following best describes the difference between mass and weight?

Accepted Answer

Mass is the amount of matter in an object, while weight is the force of gravity acting on that mass.

Question 14

A nutrition label lists 9 g of fat, 4 g of protein, and 37 g of carbohydrate in a serving. What percentage of the total mass is carbohydrate?

Accepted Answer

$$\frac{37\ \mathrm{g}}{9\ \mathrm{g} + 4\ \mathrm{g} + 37\ \mathrm{g}} 	imes 100\% = 74\%$$

Question 15

Which of the following is a trace element important for the function of hemoglobin in the human body?

Accepted Answer

Iron (Fe)

Question 16

A drop factor for an IV solution is 20 gtt/mL. If a patient needs to receive 100 mL, how many drops (gtt) should be administered?

Accepted Answer

$$100\ \mathrm{mL} 	imes 20\ \mathrm{gtt/mL} = 2000\ \mathrm{gtt}$$

Question 17

Which of the following is the correct scientific notation for 0.00056?

Accepted Answer

$$5.6 	imes 10$$^{-4}$$

Question 18

Which of the following best describes the difference between accuracy and precision?

Accepted Answer

Accuracy refers to how close a measurement is to the true value, while precision refers to how close repeated measurements are to each other.

Question 19

A sample of water has a mass of 25.0 g. What is its volume in mL, given that the density of water is $$1.00\ \mathrm{g/mL}$$?

Accepted Answer

$$\mathrm{Volume} = \frac{25.0\ \mathrm{g}}{1.00\ \mathrm{g/mL}} = 25.0\ \mathrm{mL}$$

Chemistry Basics: Matter and Measurement (Chapter 1 Study Guide)

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