Question 1

Which of the following best describes the difference between a scientific law and a scientific theory?

Accepted Answer

A law describes what happens under certain conditions, while a theory explains why it happens.

Question 2

A student mixes sand and water and then separates them using the method shown in the third image. What property allows this separation to occur?

Accepted Answer

Difference in particle size

Question 3

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

Accepted Answer

Water boiling to form steam

Question 4

A compound is best defined as:

Accepted Answer

A substance composed of two or more elements chemically combined in fixed proportions

Question 5

Which laboratory technique would be most appropriate to separate a mixture of two liquids with different boiling points, as shown in the fourth image?

Accepted Answer

Distillation

Question 6

A measurement is recorded as 25.00 cm. How many significant figures does this value have?

Accepted Answer

$$4$$

Question 7

Convert $$0.714\ \mathrm{g/mL} ($$density of diethyl ether) to $$\mathrm{kg/m^3$}.$$

Accepted Answer

$$714\ \mathrm{kg/m^3$}$$

Question 8

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

Accepted Answer

Salad with lettuce, tomatoes, and cucumbers

Question 9

A block has dimensions $$2.00\ \mathrm{cm} 	imes 5.00\ \mathrm{cm} 	imes 1.00\ \mathrm{cm}$$ and a mass of $$89.2\ \mathrm{g}. $$What is its density?

Accepted Answer

$$8.92\ \mathrm{g/cm^3$}$$

Question 10

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

Accepted Answer

Accuracy is how close measurements are to the true value; precision is how close measurements are to each other.

Question 11

Which of the following is an exact number?

Accepted Answer

The number of students in a classroom

Question 12

What is the temperature in Kelvin if the temperature is $$25\ ^\circ\mathrm{C}$$?

Accepted Answer

$$298\ \mathrm{K}$$

Question 13

Which of the following is the correct scientific notation for the number $$0.00000123$$?

Accepted Answer

$$1.23 	imes 10$$^{-6}$$

Question 14

A student needs to convert $$21\ \mathrm{lbs} to$$ $$\mathrm{kg}. $$Which conversion factor should be used?

Accepted Answer

$$1\ \mathrm{kg} = 2.205\ \mathrm{lb}$$

Question 15

Which of the following is a chemical property?

Accepted Answer

Ability to react with oxygen

Question 16

Which metric prefix represents $$10^{-9}$$?

Accepted Answer

Nano

Question 17

Which of the following best describes the process shown in the fifth and sixth images (chromatography)?

Accepted Answer

Separation based on interactions between mobile and stationary phases

Question 18

Which of the following is a derived SI unit?

Accepted Answer

Liter

Question 19

A student adds $$3.0\ \mathrm{mL}$$ and $$12.15\ \mathrm{mL}$$ together. What is the correct answer with the proper number of significant figures?

Accepted Answer

$$15.2\ \mathrm{mL}$$

Chapter 1: Chemical Foundations – General Chemistry Study Notes

Guida di studio - Domande di pratica

Study guide - Flashcard