Question 1

Which of the following statements best describes the difference between accuracy and precision in scientific measurements?

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 2

A student measures the mass of a block five times and gets the following results: 10.2 g, 10.3 g, 10.2 g, 10.3 g, 10.2 g. The actual mass is 12.0 g. How would you describe the student's measurements?

Accepted Answer

The measurements are precise but not accurate.

Question 3

How many significant figures are in the measurement 0.00450 kg?

Accepted Answer

3

Question 4

Which calculation below correctly applies the significant figure rules for multiplication and division?

$$1.25 	imes 0.032 = ?$$

Accepted Answer

$$0.040$$

Question 5

A scientist adds the following numbers: $$2.345 + 0.07 + 5.89. $$According to the rules for significant figures in addition, what is the correct answer?

Accepted Answer

$$8.30$$

Question 6

Which of the following is a derived unit in the SI system?

Accepted Answer

Liter (L)

Question 7

A sample of liquid has a mass of 25.0 g and a volume of 10.0 mL. What is its density?

Accepted Answer

$$2.5 \ \mathrm{g/mL}$$

Question 8

Which of the following is an example of an intensive property?

Accepted Answer

Density

Question 9

Convert a temperature of $$25.0^{\circ}$$\mathrm{C}$$ to Kelvin.

Accepted Answer

$$298.2 \ \mathrm{K}$$

Question 10

Which prefix multiplier represents $$10^{-3} in $$the metric system?

Accepted Answer

milli-

Question 11

Which of the following statements is a hypothesis?

Accepted Answer

If we cool the vapor, the gas should condense.

Question 12

Which of the following best describes a scientific law?

Accepted Answer

A brief statement that summarizes past observations and predicts future ones.

Question 13

Which of the following is a pure substance?

Accepted Answer

Table salt

Question 14

Which statement best explains why chemistry is important in understanding air pollution?

Accepted Answer

Chemistry helps us understand the behavior of atoms and molecules that make up pollutants.

Question 15

Which of the following is NOT a characteristic of a good scientific theory?

Accepted Answer

It is never revised or discarded.

Question 16

A student measures the temperature of a solution as $$32.0^{\circ}$$\mathrm{C}$$. What is this temperature in Fahrenheit?

Accepted Answer

$$89.6^{\circ}$$\mathrm{F}$$

Question 17

Which of the following best describes the difference between a compound and a mixture?

Accepted Answer

A compound is composed of two or more elements chemically bonded, while a mixture contains two or more substances physically combined.

Question 18

Which of the following is an example of an observation in the scientific method?

Accepted Answer

Recording the color change in a chemical reaction.

Question 19

A block of metal has a mass of 50.0 g and a volume of 20.0 cm$$^3. If $$the density of water is $$1.00 \ \mathrm{g/cm}^3$$, will the block float or sink in water?

Accepted Answer

It will sink because its density is greater than water.

Introduction to Chemistry: Measurement, Matter, and the Scientific Method

Guida di studio - Domande di pratica

Study guide - Flashcard