Chapter 2: Atoms, Molecules, Ions

Question 1

oxyanions

Answer 1

an anion containing one or more oxygen atoms bonded to another element

Question 2

ionic compounds

Answer 2

metal + nonmetal

Question 3

binary compounds

Answer 3

a two-element compound

Question 4

periods

Answer 4

go across the table; horizontal

Question 5

noble gas

Answer 5

a group of 8a elements

Question 6

halogens

Answer 6

a group of 7a elements

Question 7

alkaline earth metals

Answer 7

a group of 2a metals

Question 8

alkali metals

Answer 8

a group 1A metal

Question 9

nonmetals

Answer 9

an element not exhibiting metallic characteristics, accepts electrons from metals

Question 10

metals

Answer 10

an element that gives up electrons relatively easily and is lustrous, malleable, and a good conductor of heat and electricity

Question 11

periodic table

Answer 11

a chart showing all the elements arranged in columns with similar chemical properties

Question 12

polyatonic ion

Answer 12

an ion containing a number of atoms

Question 13

ionic bonding

Answer 13

the electrostatic attraction between oppositely charged ions

Question 14

anion

Answer 14

a negatively charged atom

Question 15

cation

Answer 15

a positively charged ion

Question 16

ion

Answer 16

an atom or a group of atoms that has a net positive or negative charge

Question 17

ball-and-stick model

Answer 17

a molecular model that distorts the sizes of atoms, but shows bond relationships clearly

Question 18

space-filling model

Answer 18

a model of a molecule showing the relative size of the atoms and their relative orientations

Question 19

structural formula

Answer 19

the representation of a molecule in which the relative positions of the atoms are shown and the bonds are indicated by lines

Question 20

chemical formula

Answer 20

the representation of a molecule in which the symbols for the elements are used to indicate the types of atoms present and subscripts are used to show that relative number of atoms

Question 21

molecule

Answer 21

a bonded collection of two or more atoms of the same or different elements

Question 22

covalent bonds

Answer 22

a type of bonding in which electrons are shared between the atoms

Question 23

chemical bonds

Answer 23

the energy that holds two atoms together in a compound

Question 24

mass number

Answer 24

the total number of protons and neutrons in the atomic nucleus of an atom

Question 25

atomic number

Answer 25

the number of protons in the nucleus of an atom

Question 26

isotopes

Answer 26

atoms of the same element (the same number of protons) with different numbers of neutrons. They have an identical atomic numbers but different mass numbers

Question 27

neutrons

Answer 27

a particle in the atomic nucleus with mass virtually equal to the proton’s but with no charge

Question 28

protons

Answer 28

a positively charged particle in an atomic nucleus

Question 29

nucleus

Answer 29

the small dense center of positive charge in an atom

Question 30

nuclear atom

Answer 30

an atom having a dense center of positive charge (the nucleus) with electrons moving around the outside

Question 31

radioactivity (radio active decay)

Answer 31

the spontaneous decomposition of a nucleus to form a different nucleus

Question 32

electrons

Answer 32

a negatively charged particle that moves around the nucleus of an atom

Question 33

cathode rays

Answer 33

the “rays” emanating from the negative electrode in a partially evacuated tube; a stream of electrons

Question 34

Avogadro’s law

Answer 34

equal volumes of gasses at the same temperature and pressure contain the same number of particles

Question 35

atomic mass

Answer 35

the weighted average mass of the atoms in a naturally occurring elements

Question 36

law of multiple proportions

Answer 36

when two elements form a series of compounds, the ratios of the masses of the second element that combine with one gram of the first element can always be reduced to small whole numbers

Question 37

law of definite proportion

Answer 37

a given compound always contains exactly the same proportion of elements by mass

Question 38

law of conservation of mass

Answer 38

mass CANNOT be created or destroyed