Exam 1

Question 1

Properties of metals

Answer 1

• Solids at room temperature (exception Hg)
• Conduct electricity and heat very well
• Very high melting points

Question 2

Properties of non-metals

Answer 2

• Solids, liquids, or gases at room temperature
• Poor conductors of heat and electricity
• Lower melting points than metals.

Question 3

Properties of metalloids

Answer 3

-Gradual change between metals and nonmetals

Question 4

Atom

Answer 4

The smallest identifiable unit of an element

Question 5

Molecule

Answer 5

Two or more atoms chemically joined in a specific arrangement.

Question 6

Properties of solids

Answer 6

• Atoms are packed together very closely and very tightly.
• Atoms can vibrate, but do not move past one another
• Solids have a fixed volume and fixed shape

Question 7

Properties of liquids

Answer 7

• Not as tightly packed as solids
• Free to move past one another
• Shape is variable, but volume is fixed

Question 8

Properties of gases

Answer 8

• Lots of space between atoms
• Free to move anywhere
• Shape and volume are variable

Question 9

Pure substance

Answer 9

Something that is composed of only a single type of atom or molecule.
Ex: Cu or H20

Question 10

Element

Answer 10

A substance that cannot be broken down into other atoms.

Question 11

Compound

Answer 11

Substance that may be broken down into other elements.
Ex: H2O –> 2H, O
CO2

Question 12

Mixture

Answer 12

Two or more elements/atoms or compounds/molecules present in variable proportions
(Coffee, chicken noodle soup.)

Question 13

Heterogeneous Mixture

Answer 13

Composition varies throughout the sample

chicken noodle soup

Question 14

Homogenous Mixture

Answer 14

Uniform composition throughout mixture (tea, wine)

Question 15

Physical Change

Answer 15

Change in the state/phase/or appearance

ice cube->water->steam

Question 16

Physical Property

Answer 16

A property that can be displayed without changing the chemical composition
Ex: color, odor, phase at RM,MP,BP

Question 17

Chemical Change

Answer 17

Change in composition of matter. It becomes a different substance
Fe2+car->Rust

Question 18

Chemical Property

Answer 18

Substance is changed to a new substance

Burnt match, curdled milk

Question 19

Mass

Answer 19

A measure of the quantity of mass or matter in an object

Question 20

Weight

Answer 20

A measure of the gravitational pull on an object

Question 21

Temperature

Answer 21

A measure of the kinetic energy (energy of motion) of the atoms or molecules.

Question 22

D=

Answer 22

Mass/Volume (Mass=Density*Volume)

Question 23

Volume=

Answer 23

LWH (1cm3= 1mL)

Question 24

Precision

Answer 24

How clue together your data points are

Question 25

Accuracy

Answer 25

How close your value is to the true value

Question 26

Systematic Error

Answer 26

Consistent error

Question 27

Law of Conservation of Mass

Answer 27

In a chemical reaction, matter is neither created or destroyed.

Question 28

Law of Definite Proportions

Answer 28

A compound is always made up of the same relative masses of the elements that compose it. Water will always be 2H, 1O

Question 29

Law of Multiple Proportions

Answer 29

Any time two or more elements combine in different ratios, a different compound is formed.

Question 30

Atomic Theory

Answer 30

- Each element is composed of tiny indestructible particles called atoms - All atoms of a given element have the same mass and other properties that distinguish them from atoms of a different element - Atoms combine in simple whole number ratios to form compounds - Atoms of one element cannot change into atoms of another element.

Question 31

Nuclear Theory

Answer 31

- Atoms are mostly empty space - There are small, dense regions in the atoms (nucleus) - Protons present to make the atom neutral.

Question 32

Atomic Number

Answer 32

-# of protons in the nucleus.

Question 33

Isotopes

Answer 33

Atoms with the same number of protons (the same element) but have different number of neutrons.

Question 34

Ion

Answer 34

Charged particle

Question 35

anion

Answer 35

Non-metal. Negative charge. Tend to gain electrons.

Question 36

Cation

Answer 36

Metal. Positive charge. Tend to lose electrons

Question 37

Ionic Bond

Answer 37

Formed between cations and anions (metals and nonmetals). Opposite charges are attracted to each other, and is what holds them together. Usually very hard to break

Question 38

Covalent Bond

Answer 38

Atoms are all non-metals; share electrons

Question 39

Empirical Formula

Answer 39

Gives the relative number of elements in a compound in the simplest whole number ratio

Question 40

Molecular Formula

Answer 40

Gives the actual number of elements in a compound

Question 41

Molecular elements

Answer 41

two or more atoms of the same element bonded together are the base units. Diatomic elements: H O N F Cl Br I

Question 42

Ionic compounds

Answer 42

Form ionic bonds (between metal and nonmetal)

Question 43

Covalent compounds

Answer 43

two or more nonmetal covalently boned

Question 44

Oxyanion

Answer 44

Compound that contains oxygen and one other element (most polyatomic ions are oxyanions)

Question 45

Combustion Analysis

Answer 45

A reaction in which a compound burns in the presence of oxygen to give carbon dioxide and water