Key Terms Unit 1

Question 1

The study of the composition, structure, properties, and changes of matter

Answer 1

Chemistry

Question 2

Molecule

Answer 2

An entity composed of two or more atoms with the atoms attached to one another in a specific way

Question 3

Property

Answer 3

Any characteristic that gives a sample of matter its unique identity

Question 4

Atom

Answer 4

small building blocks of matter

Question 5

Matter

Answer 5

The physical material of the universe; Anything that has mass and occupies space

Question 6

States of Matter

Answer 6

Solid, Liquid, and gas

Question 7

gas (vapor)

Answer 7

has no fixed volume or shape. Conforms to the volume and shape of its container

Question 8

Liquid

Answer 8

has a distinct volume independent of its container but has no specific shape

Question 9

Solid

Answer 9

has both a definite shape and a definite volume

Question 10

Pure Substance

Answer 10

matter that has distinct properties and a composition that does not vary from sample to sample

Question 11

Elements

Answer 11

Substances that cannot be decomposed into smaller substances

Question 12

Compounds

Answer 12

substances composed of two or more elements. They contain to or more kinds of atoms. Ex: water

Question 13

Mixtures

Answer 13

Combinations of two or more substances in which each substance retains its chemical identity

Question 14

Physical Properties

Answer 14

Properties observed without changing the identity and composition of the substance (boiling point, hardness, color, odor)

Question 15

Chemical Properties

Answer 15

describes the way a substance may change, or react, to form other substances. (Flammability)

Question 16

Intensive Properties

Answer 16

Do not depend on the amount of sample being being examined

Question 17

Extensive Properties

Answer 17

Depend on the amount of the sample, with two samples being mass and volume

Question 18

Physical Change

Answer 18

Changes in physical appearance but not chemical composition

Question 19

Changes of State are what type of change?

Answer 19

Physical

Question 20

Chemical Change

Answer 20

A substance is transformed into a chemically different substance.

Question 21

Density

Answer 21

The amount of mass in a unit volume of a substance: D=M/V. The units will typically be in g/cm^3 or g/mL

Question 22

cm^3 is equivalent to

Answer 22

mL

Question 23

Precision

Answer 23

A measure of how closely individual measurements agree with one another

Question 24

Accuracy

Answer 24

How closely individual measurements agree with the correct or true value

Question 25

Significant Figures

Answer 25

All digits of a measured quantity, including the uncertain ones

Question 26

Conversion Factor

Answer 26

A fraction whose numerator and denominator are the same quantity expressed in different units (2.54cm= 1in) Given Unit x Desired Unit/Given Unit= desired unit

Question 27

Periodic Table

Answer 27

The arrangement of elements in order of increasing atomic number, with elements having similar properties placed in vertical columns

Question 28

Periods

Answer 28

Horizontal row of the periodic table

Question 29

Groups

Answer 29

Columns of the periodic table

Question 30

Metallic Elements

Answer 30

(except Hydrogen) all of the elements on the left and in the middle of the periodic table

Question 31

Properties of Metallic Elements

Answer 31

Luster, heat conduction, electricity conduction, and solid at room temperature (except mercury)

Question 32

Alkali Metals

Answer 32

Li, Na, K, Rb, Cs, Fr

Question 33

Alkaline Earth Metals

Answer 33

Be, Mg, Ca, Sr, Ba, Ra

Question 34

Chalcogens

Answer 34

O, S, Se, Te Po

Question 35

Halogens

Answer 35

F, Cl, Br, I, At

Question 36

Noble Gasses

Answer 36

He, Ne, Ar, Kr, Xe, Rn

Question 37

Diatomic Molecules

Answer 37

H2,O2,N2, F2, Cl2, Br2, and I2

Question 38

Molecular Formulas

Answer 38

Chemical Formulas that indicate the actual numbers of atoms in a molecule

Question 39

Empirical Formulas

Answer 39

Chemical Formulas that give only the relative number of atoms of each type in a molecule

Question 40

Structural Formula

Answer 40

Shows which atoms are attached to which (visually)

Question 41

Ion

Answer 41

Electrons are removed from or added to an atom, a charged particle is formed

Question 42

An Ion with a positive charge

Answer 42

Cation

Question 43

An ion with a negative charge

Answer 43

Anion