Question 1

Which of the following best describes a chemical change?

Accepted Answer

Iron rusting when exposed to air

Question 2

A sample of matter is uniform in appearance and composition, but can be separated into its components by physical means. Which classification best fits this sample?

Accepted Answer

Homogeneous mixture

Question 3

Which of the following is the correct chemical symbol for sodium, and what is the origin of this symbol?

Accepted Answer

Na, from the Latin name 'natrium'

Question 4

A patient’s temperature is measured as $$104\ ^\circ \mathrm{F}. $$What is this temperature in degrees Celsius? (Use $$^\circ \mathrm{C} = \frac{5}{9} ( ^\circ \mathrm{F} - 32 ))$$

Accepted Answer

$$40\ ^\circ \mathrm{C}$$

Question 5

Which of the following statements about density is correct?

Accepted Answer

Density is mass divided by volume, and is usually expressed in $$\mathrm{g/cm^3$}$$ for solids.

Question 6

A clinical laboratory reports a blood sample contains $$0.000101 g of $$iron. Express this value in micrograms ($$\mug).$$

Accepted Answer

$$101\ \mu\mathrm{g}$$

Question 7

Which of the following measurements contains three significant figures?

Accepted Answer

0.0834 cm

Question 8

A patient weighing 160 lb is prescribed a medication at a dosage of $$20\ \mu\mathrm{g}/\mathrm{kg}$$ body weight. How many milligrams of medication should the patient receive? (1 kg = 2.205 lb)

Accepted Answer

$$1.45 mg$$

Question 9

Which of the following is a derived SI unit?

Accepted Answer

Gram per cubic centimeter ($$\mathrm{g/cm^3$})$$

Question 10

A sample of isopropyl alcohol has a mass of $$25.0 g $$and a density of $$0.7855\ \mathrm{g/mL}. $$What is its volume in mL? (Round to three significant figures.)

Accepted Answer

$$31.8 mL$$

Question 11

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

Accepted Answer

Mass is the amount of matter in an object; weight is the gravitational force acting on that mass.

Question 12

Convert $$0.50$$ quarts to deciliters. (1 qt = 946 mL, 1 dL = 100 mL)

Accepted Answer

$$4.7 dL$$

Question 13

Which of the following is an example of a heterogeneous mixture?

Accepted Answer

Salad with lettuce, tomatoes, and cucumbers

Question 14

A bath uses $$95 kg of $$water, which is heated from $$15\ ^\circ \mathrm{C} to$$ $$40\ ^\circ \mathrm{C}. $$How many calories are required? (Specific heat of water = $$1.00\ \mathrm{cal/g\ ^\circ C})$$

Accepted Answer

$$2,375,000$$ cal

Question 15

Which of the following statements about the SI and metric systems is correct?

Accepted Answer

The SI unit of mass is the kilogram, while the metric unit of mass is the gram.

Question 16

A nurse needs to administer $$0.012 g of a $$painkiller available as a $$15\ \mathrm{mg/mL}$$ solution. How many mL should be administered?

Accepted Answer

$$0.80 mL$$

Question 17

Which of the following is the correct scientific notation for $$0.000000120 m$$?

Accepted Answer

$$1.20 	imes 10$$^{-7}$$ m

Question 18

A student records a measurement as $$3400 kg. $$According to the rules of significant figures, how many significant figures does this value have?

Accepted Answer

It may have two, three, or four significant figures, depending on context.

Question 19

Which of the following is the correct relationship for converting Celsius to Kelvin?

Accepted Answer

$$K = ^\circ C + 273.15$$

Question 20

A hydrometer is used in medicine to measure the specific gravity of urine. If a urine sample has a specific gravity of $$1.025$$, what does this mean?

Accepted Answer

The urine is 1.025 times as dense as water at the same temperature.

Chapter 1: Matter and Measurements – GOB Chemistry Study Notes

Guida di studio - Domande di pratica

Study guide - Flashcard