Question 1

Which of the following statements about the periodic table is correct?

Accepted Answer

Elements are organized by increasing atomic number.

Question 2

A student measures the mass of a metal block as 45.2 g and its volume as 12.0 mL. What is the density of the block?

Accepted Answer

$$d = \frac{45.2\ \mathrm{g}}{12.0\ \mathrm{mL}} = 3.77\ \mathrm{g/mL}$$

Question 3

Which of the following is an example of an ionic bond?

Accepted Answer

The bond in $$\mathrm{NaCl}$$

Question 4

Which SI unit would you use to measure the amount of a chemical substance?

Accepted Answer

Mole

Question 5

A sample of gas occupies a volume of 2.50 L and has a mass of 5.00 g. What is its density?

Accepted Answer

$$d = \frac{5.00\ \mathrm{g}}{2.50\ \mathrm{L}} = 2.00\ \mathrm{g/L}$$

Question 6

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

Accepted Answer

An element contains only one type of atom; a compound contains two or more types of atoms chemically combined.

Question 7

Which of the following is NOT a correct SI base unit and its quantity?

Accepted Answer

Gram – mass

Question 8

A chemist records a measurement as 0.04050 g. How many significant figures does this value have?

Accepted Answer

4

Question 9

Which statement about the structure of an atom is correct?

Accepted Answer

Protons and neutrons are found in the nucleus; electrons orbit the nucleus.

Question 10

Which of the following is a real-life example of a covalent bond?

Accepted Answer

The bond between hydrogen and oxygen in water

Question 11

A student mixes two clear solutions and observes the formation of a white solid. Which statement best explains this observation?

Accepted Answer

A chemical reaction has occurred, producing a compound.

Question 12

Which of the following best describes the process of measuring the mass of a liquid using a balance?

Accepted Answer

Measure the mass of the empty container, add the liquid, and subtract the mass of the container from the total mass.

Question 13

Which of the following is a pure substance?

Accepted Answer

Carbon dioxide ($$\mathrm{CO_2$})$$

Question 14

A sample of ethanol has a mass of 78.5 g and a volume of 100.0 mL. What is its density?

Accepted Answer

$$d = \frac{78.5\ \mathrm{g}}{100.0\ \mathrm{mL}} = 0.785\ \mathrm{g/mL}$$

Question 15

Which of the following is the correct definition of density?

Accepted Answer

Density is mass divided by volume.

Question 16

Which of the following is a correct statement about significant figures?

Accepted Answer

Zeros between nonzero digits are significant.

Question 17

Which of the following best explains why water is considered a compound?

Accepted Answer

It can be separated into hydrogen and oxygen by chemical means.

Question 18

Which of the following is a real-world application of the concept of density?

Accepted Answer

Identifying whether an object will float or sink in water.

Question 19

Which of the following best describes the difference between ionic and covalent bonds?

Accepted Answer

Ionic bonds involve transferring electrons; covalent bonds involve sharing electrons.

Matter, Measurements, and Atomic Structure: General Chemistry Study Guide

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