Midterm 1 vocab

Question 1

chemistry

Answer 1

the scientific study of the properties, composition, and structure of matter, the transformations matter undergoes, and the energy of these processes

Question 2

matter

Answer 2

anything that has mass and occupies space

Question 3

mass

Answer 3

a measure of the amount of matter in an object

Question 4

weight

Answer 4

a measure of the gravitational pull on an object

Question 5

physical process

Answer 5

acts on the physical state of matter but doesn’t change its chemical identity (atoms and bonds between them remain the same)

Question 6

molecule

Answer 6

an assembly of two or more atoms held together in a characteristic pattern by chemical bonds

Question 7

Law of Constant Composition

Answer 7

every sample of a compound contains the same elements combined in the same proportions

Question 8

intensive properties + example

Answer 8

properties that are independent of the amount of substance (ex. hardness, density, phase transition temperature)

Question 9

extensive properties + example

Answer 9

properties that depend on the amount of a substance present (mass, length, width, volume, etc)

Question 10

physical properties

Answer 10

can be determined without changing a substance into a different substance

Question 11

chemical properties

Answer 11

can only be observed by reacting a substance to form a new substance in a chemical reaction

Question 12

precision

Answer 12

how consistent your results are (less random error, the more precision)

Question 13

random error

Answer 13

error that produces inconsistent measured values of a constant quantity (can only be determined from a set of at least two repeated measurements)

Question 14

accuracy

Answer 14

how close you are to the “correct” value

Question 15

pure substance

Answer 15

has constant composition

Question 16

mixtures

Answer 16

composition varies by sample

Question 17

elements

Answer 17

substances made up of one type of atom

Question 18

compounds

Answer 18

substances made up of more than one type of atom

Question 19

heterogeneous mixture

Answer 19

a physical combination that is not uniform

Question 20

homogeneous mixture

Answer 20

a physical combination that is uniform

Question 21

solids

Answer 21

have defined volume and shape

Question 22

liquid

Answer 22

have defined volume, no definite shape

Question 23

gas

Answer 23

no definite volume or definite shape

Question 24

a solid ____ turns into gas

Answer 24

subliming

Question 25

a gas _____ turns into a solid

Answer 25

depositing

Question 26

a gas ____ turns into a liquid

Answer 26

condensing

Question 27

heterogeneous mixtures can be separated by...

Answer 27

centrifugation or filtration

Question 28

homogeneous mixtures can be separated by

Answer 28

distillation or evaporation

Question 29

orbitals

Answer 29

the 3D areas of space that electrons can occupy around the nucleus

Question 30

The scientific method outlines...

Answer 30

how we form and test hypotheses to create scientific theories and models

Question 31

Dimensional analysis

Answer 31

unit conversions

Question 32

scientific notation

Answer 32

a more convenient way to write out and compare very large and very small numbers

Question 33

John Dalton's atomic theory stated

Answer 33

elements are made of indivisible small particles called atoms; different elements are composed of different kinds of atoms

Question 34

_____ _____ dictates the properties of different elements

Answer 34

atomic structure

Question 35

What conclusion resulted from Thompson's Cathode Ray Tube experiment?

Answer 35

electrons are negatively charged and highly charged and extremely light

Question 36

Who proposed the plum pudding model

Answer 36

Thompson

Question 37

Describe beta particles

Answer 37

have the same charge-to-mass ratio and negative charge as electrons, are therefore high-energy electrons

Question 38

Describe alpha particles

Answer 38

have twice as much charge and the opposite sign as an electron (+2) and are 10^3 times heavier

Question 39

What kind of particles did Rutherford use in his Gold Foil Experiment?

Answer 39

Alpha particles

Question 40

Describe Rutherford's Gold Foil Experiment

Answer 40

Alpha particles were shot at a piece of gold foil and most particles passed directly through the foil, meaning most of the space in the gold foil was empty, and very rarely an alpha particle was deflected strongly from the foil, which means the gold foil also contained occasional small, dense, highly charged centers that strongly deflect alpha particles

Question 41

Describe Rutherford's nuclear model

Answer 41

A positively charge is contained in the atomic nucleus at the center, surrounded by a diffuse cloud of negatively charged electrons

Question 42

Describe Protons

Answer 42

center of atom(nucleus), approx 1 atomic mass unit, positive charge

Question 43

atomic number equals the amount of ___

Answer 43

protons

Question 44

Describe Neutrons

Answer 44

center of atom(nucleus), approx 1 atomic mass unit, no charge

Question 45

the atomic mass number equals ____

Answer 45

neutrons + # protons

Question 46

the _____ _____ is used to tell the difference between isotopes

Answer 46

mass number

Question 47

Describe electrons

Answer 47

found outside the nucleus, approx 0 atomic mass unit, negative charge

Question 48

A neutral atom has this ratio of protons to electrons

Answer 48

equal

Question 49

if you change the number of electrons, you will form an ____

Answer 49

ion

Question 50

Cations have a ____ charge because they have more _____

Answer 50

positive, protons

Question 51

Anions have a ____ charge because they have more _____

Answer 51

negative, electrons

Question 52

The charge is written on the ____ _____ of the chemical symbol

Answer 52

upper right

Question 53

The average atomic mass equals

Answer 53

the average mass of isotope 1, and so on for the other stable elements

Question 54

Each orbital can contain up to ___ electrons

Answer 54

2

Question 55

Electrons can only exist at the discrete energy levels of the orbitals, so the energy of an electron is ____

Answer 55

quantized

Question 56

The further an electron is from the nucleus, the ____ the energy.

Answer 56

higher

Question 57

Orbitals of an atom are defined by which quantum numbers

Answer 57

n, l, ml, ms

Question 58

Amount of total nodes =

Answer 58

n - 1

Question 59

define n

Answer 59

which shell the orbital belongs to; how far away the electron is from the nucleus

Question 60

orbitals in the same shell have the same value of ___

Answer 60

n

Question 61

define node

Answer 61

an area where no electron can exist

Question 62

define radial node

Answer 62

a spherical shell that never passes through the nucleus (origin)

Question 63

define angular node

Answer 63

a plane or a cone that always pass through the nucleus

Question 64

what are the two kinds of nodes? which one passes through the nucleus, and which one doesn't?

Answer 64

Radial and Angular; radial does not pass through the nucleus, angular does

Question 65

Nodes ____ the energy of the orbital

Answer 65

increase (the less close space to the nucleus the farther the electrons must be and therefore higher energy)

Question 66

What value equals the # of angular nodes?

Answer 66

L

Question 67

what does l define?

Answer 67

The shape of an orbital