unit one definitions

Question 1

chemistry

Answer 1

field of science that examines the properties and behavior of matter, as well as the change of matter

Question 2

what is the scientific method

Answer 2

the path that leads from experiments, hypotheses, and observations into theories or laws

Question 3

what is the pathway of the scientific method?

Answer 3

questions/observations -> hypothesis -> experimental tests -> repeatable results that either support or refute the hypothesis

Question 4

observation

Answer 4

something you notice in nature or an experiment

Question 5

hypothesis

Answer 5

a tentative explanation or prediction based on observations. MUST be falsifiable to be considered scientific

Question 6

experiment

Answer 6

carried out to test a hypothesis

Question 7

Theory (model)

Answer 7

a set of assumptions put forth to EXPLAIN some aspect of observed behavior.

why/how

Question 8

law

Answer 8

concise statement or summary of generally observed behavior that is always the same under the same conditions.

describing WHAT will occur

Question 9

law vs theory

Answer 9

a law is a summary of what happens.

a theory is an attempt to explain WHY it happens

Question 10

matter

Answer 10

anything that has mass and takes up space

Question 11

solid

Answer 11

rigid, fixed volume and shape, slightly compressible.

solid particles have some energy which causes them to vibrate back-and-forth however, they rarely move past neighboring particles

Question 12

liquid

Answer 12

definite volume, no definite shape (assumes shape of container), slightly compressible.

particles are arranged randomly and can FLOW past each other

Question 13

gas

Answer 13

no fix volume or shape (assumes volume and shape of container), highly compressible

particles fly around, colliding with one another and the walls of the container

Question 14

gas

Answer 14

no fix volume or shape (assumes volume and shape of container), highly compressible

particles fly around, colliding with one another and the walls of the container

Question 15

Qualitative examples

Answer 15

color, smell, appearance, etc.

Question 16

quantitative examples

Answer 16

volume, speed, time, mass

Question 17

pure substance

Answer 17

a substance with a constant composition (ex. water, sugar, etc)

can further be broken down into compounds and elements

Question 18

compound

Answer 18

two or more DIFFERENT atoms joined together by chemical bonds in fixed ratios

(ex H2O, CaCO3, LiCl, etc)

Question 19

Elements

Answer 19

substance that cannot be further broken down into anything simpler, composed of a single type of atom

(ex. He, Ni, Mg, etc.)

Question 20

what are the diatonics

Answer 20

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

(should also know P4 and S8)

Question 21

molecules

Answer 21

two or more atoms (can be the same or different) held together by chemical bonds

Question 22

molecules vs compounds

Answer 22

molecule: two or more of the same type of element

compound: two or more different types of elements

Question 23

Mixture

Answer 23

consists of two or more pure substances that have variable composition and can be separated by physical techniques
(ex. wood, gasoline, soil, etc.)

there are two types of mixtures

Question 24

homogeneous mixture

(aka solutions)

Answer 24

having visibly indistinguishable parts.

two or more substances in the same phase, evenly distributed, constant composition
(ex. Saltwater)

Question 25

Heterogeneous mixture

Answer 25

having visibly distinguishable parts. components are unevenly distributed and there is not a constant composition throughout (ex. sweet tea and ice)

Question 26

know the difference between pure substances and homogeneous mixtures

Question 27

Distillation

Answer 27

A method of separation that depends on the boiling points of a liquid mixture to separate them this is a good option when the components of the mixture have different boiling points

Question 28

Filtration

Answer 28

simple method of separating a solid and liquid. The mixture is passed through a mesh, allowing the liquid to pass, leaving behind the solid.

Question 29

chromatography

Answer 29

method to separate a liquid or gaseous phase.

Question 30

Law of conservation of mass

Answer 30

mass is neither created nor destroyed

Question 31

Law of conservation of mass

Answer 31

mass is neither created nor destroyed

Question 32

law of definite proportion (or constant composition)

Answer 32

A given compound always contains the same proportion of elements by mass

Question 33

extensive property

Answer 33

A property that depends on the amount of matter in a sample (ex. mass, volume, length)

Question 34

Intensive property

Answer 34

A property that is independent on the amount of matter in a sample (ex. Color, density, boiling point, melting point, molar mass)

Question 35

Density

Answer 35

The mass of a substance per unit of volume d = mass/volume

Question 36

Physical change

Answer 36

change in the form of a substance (state or size/shape), but not an actual chemical composition

Question 37

Physical change examples

Answer 37

ice, melting, water boiling off, cutting a sheet of paper

Question 38

Chemical change

Answer 38

Changing the chemical composition of a substance

Question 39

Chemical change examples

Answer 39

Iron rusting, woodburning, baking, a cake, removing carbon from carbon dioxide, lighting a match

Question 40

Kinetic molecular theory of matter

Answer 40

as matter gains energy, it’s temperature increases. As temperature increases the average kinetic energy of the particles also increases. As the kinetic energy increases matter, transforms from solid, two liquid, to gas.

Question 41

which state of matter has the most kinetic energy? Which has the least?

Answer 41

The gas phase has the most kinetic energy and solid has the least

Question 42

Energy

Answer 42

The capacity to do work or transfer heat

Question 43

Kinetic energy

Answer 43

energy because of motion, dependent on the mass and velocity of an object

Question 44

Thermal energy

Answer 44

The form of kinetic energy associated with heat in matter

Question 45

potential energy

Answer 45

Energy due to position in space or composition. The energy stored in chemical bonds is a type of potential energy.

Question 46

accuracy vs precision

Answer 46

accuracy: the true value precision: involves several measurements and how similar they are. Looks at reproducibility

Question 47

accuracy vs precision

Answer 47

accuracy: the true value precision: involves several measurements and how similar they are. Looks at reproducibility

Question 48

what is an isotopes

Answer 48

Isotopes are versions of a particular element that have different numbers of neutrons

Question 49

ions

Answer 49

Ions are atoms (or molecules) that have lost or gained electrons and have an electrical charge.