Question 1

Which of the following best describes a sample of air at sea level?

Accepted Answer

A homogeneous mixture

Question 2

Which of the following statements about isotopes is correct?

Accepted Answer

Isotopes of an element have the same number of protons but different numbers of neutrons.

Question 3

A patient receives a dose of $$5.0\ \mu Ci of a $$radioisotope with a half-life of 6 hours. How much of the radioisotope remains after 18 hours?

Accepted Answer

$$0.625\ \mu Ci$$

Question 4

Which of the following is the correct balanced equation for the beta decay of $$^{14}_{6}C$$?

Accepted Answer

$$^{14}_{6}C \$$rightarrow ^{14}$$_{7}N $$+ ^{0}$$_{-1}\beta$$

Question 5

Which of the following compounds is ionic?

Accepted Answer

$$\mathrm{NaCl}$$

Question 6

How many atoms of oxygen are present in one formula unit of $$\mathrm{Al}_2(SO_4$)_3$$?

Accepted Answer

12

Question 7

A sample of ethanol has a mass of $$46.0\ \mathrm{g}$$ and a volume of $$58.0\ \mathrm{mL}. $$What is its density?

Accepted Answer

$$0.793\ \mathrm{g/mL}$$

Question 8

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

Accepted Answer

Elements in the same group have similar chemical properties.

Question 9

What is the correct name for $$\mathrm{FeCl}_3$$?

Accepted Answer

Iron(III) chloride

Question 10

Which of the following molecules is nonpolar?

Accepted Answer

$$\mathrm{CO}_2$$

Question 11

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

Accepted Answer

$$298.2\ \mathrm{K}$$

Question 12

How many moles are in $$18.0\ \mathrm{g} of $$water ($$\mathrm{H}_2O$$)? (Molar mass of $$\mathrm{H}_2O = 18.0\ \mathrm{g/mol})$$

Accepted Answer

1.00

Question 13

Which of the following best describes the energy stored in a stretched rubber band?

Accepted Answer

Potential energy

Question 14

Which of the following is the correct Lewis structure for methane ($$\mathrm{CH}_4$$)?

Accepted Answer

A central C atom with four single bonds to four H atoms

Question 15

A solution contains $$5.0\ \mathrm{g} of $$NaCl in $$100.0\ \mathrm{g} of $$water. What is the percent by mass of NaCl in the solution?

Accepted Answer

$$4.8\%$$

Question 16

Which of the following ions has the same electron configuration as neon ($$\mathrm{Ne}$$)?

Accepted Answer

$$\mathrm{Na}^+$$

Question 17

Which of the following is a property of metals?

Accepted Answer

They are good conductors of electricity.

Question 18

What is the molar mass of $$\mathrm{Ca(OH)_2}$$?

Accepted Answer

$$74.1\ \mathrm{g/mol}$$

Question 19

Which of the following best explains why $$\mathrm{H}_2O is a $$polar molecule?

Accepted Answer

It has polar bonds and a bent molecular shape.

Question 20

A thermometer reads $$98.6\ ^\circ\mathrm{F}. $$What is this temperature in Celsius?

Accepted Answer

$$37.0\ ^\circ\mathrm{C}$$

CHEM 102 Test 1 Study Guide: Chapters 1-3 (Matter, Atoms, Compounds)

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