Question 1

Which of the following best describes a compound?

Accepted Answer

A substance composed of two or more elements chemically combined in a fixed ratio.

Question 2

Which of the following is an example of a physical property that can be used to distinguish between different states of matter?

Accepted Answer

Density

Question 3

A student measures the mass of a metal sample as $$12.34 g $$and its volume as $$4.1 mL. $$What is the density of the metal, reported with the correct number of significant figures?

Accepted Answer

$$3.0 g/mL$$

Question 4

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

Accepted Answer

Elements are arranged by increasing atomic number.

Question 5

Which of the following best describes the difference between an ionic bond and a covalent bond?

Accepted Answer

Ionic bonds involve transfer of electrons from a metal to a nonmetal, while covalent bonds involve sharing of electron pairs between atoms.

Question 6

A sample of water has a mass of $$250 g $$and occupies a volume of $$250 mL. $$What is the density of water in this sample?

Accepted Answer

$$1.0 g/mL$$

Question 7

Which of the following is the correct SI unit for temperature?

Accepted Answer

Kelvin

Question 8

A chemist needs to prepare $$0.500$$ mol of carbon dioxide ($$\mathrm{CO_2$}). $$Which SI base unit should be used to measure the amount of substance?

Accepted Answer

Mole

Question 9

Which of the following statements about atoms is correct?

Accepted Answer

Protons and neutrons are located in the nucleus, while electrons orbit the nucleus.

Question 10

A student records the following measurements: $$2.50 m$$, $$0.0030 m$$, and $$4.0 m. $$How many significant figures are in the sum of these measurements?

Accepted Answer

2

Question 11

Which of the following is a pure substance?

Accepted Answer

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

Question 12

A hospital stores oxygen gas in a tank. If the tank contains $$16.0 kg of $$oxygen and the volume is $$12.5 L$$, what is the density of the oxygen in the tank?

Accepted Answer

$$1.28 kg/L$$

Question 13

Which of the following is NOT an SI base unit?

Accepted Answer

Gram

Question 14

Which of the following best explains why water ($$\mathrm{H_2O}) is $$considered a compound and not an element?

Accepted Answer

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

Question 15

A student is asked to identify the number of significant figures in the measurement $$0.00450 g. $$What is the correct answer?

Accepted Answer

3

Question 16

Which of the following real-world scenarios best illustrates the concept of an ionic bond?

Accepted Answer

The formation of table salt ($$\mathrm{NaCl}) $$from sodium and chlorine.

Question 17

Which of the following is the correct formula for calculating density?

Accepted Answer

$$d = \frac{m}{V}$$

Question 18

A sample of ethanol has a density of $$0.789 g/mL. If a $$laboratory technician needs $$50.0 g of $$ethanol, what volume should be measured out?

Accepted Answer

$$63.4 mL$$

Question 19

Which of the following best describes the composition of the nucleus of an atom?

Accepted Answer

Protons and neutrons

Question 20

A chemist mixes two clear liquids and observes the formation of a white solid. Which of the following best explains what has occurred?

Accepted Answer

A chemical reaction forming a new compound.

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

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