Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

chemistry > unit 3 - chem math > Flashcards

unit 3 - chem math Flashcards

1
Q

mole

A
  • a mole represents a number
  • 1 mole = 6.02 x 10^23
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

mass of an atom is in

A

AMU

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

mass of a mole of atoms is in

A

grams

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

when converting moles to anything

A

MOLEtiply

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

when converting TO moles

A

divide

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

gram formula mass

A
  • mass of 1 mole
  • the mass of a substance expressed in grams instead of AMU
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

molar mass

A

gfm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

% composition

A

the amount of an element in a compound expressed as a %

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

hydrate

A

is a salt that has a definite amount of water molecules embedded into its structure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

anhydrous salt

A

what we are left with after heating a hydrate and the water evaporates

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

molecular formula

A
  • true formula for a compound
  • exact number of atoms of each element in the compound
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

empirical formula

A

simplest whole # ratio of compound

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

to find the ratio of molecular to empirical…

A

molecular mass/empirical mass

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

1 mole of any gas occupies

A

22.4 liters at STP

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

stoichiometry

A

the area of chem math where we take a balanced chemical equation to use mole ratios (coefficients) to make predictions about the products of the reaction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

1 step stoichiometry problems are

A
  • mole to mole
  • liter to liter
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

limiting reagent problems

A

a reactant is in short supply

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

hint about determine LR problems

A

LR problems will give you the masses of each reactant

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

elements

A

made of one kind of atom

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

compound

A

substance made of two or more elements that are chemically combined

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

ionic compounds

A

form between positive and negative ions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

when do u use roman numerals

A

always use a roman numeral to designate the charge on metals with multiple oxidation states

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

molecules

A

made of 2 NON METALS held together by covalent bonds

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

covalent bonds prefix vowel rule

A

drop the o or a in the prefix name if the element begins with a vowel

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

ammonia

A

NH3

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

hydrogen peroxide

A

H2O2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

subscripts

A

number written below and to the right of a chemical symbol, shows the number of atoms of each element

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

chemical formula

A

a shorthand notation for a compound or diatomic element

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

chemical equation

A

a representation of a chemical reaction where the reactants and products are expressed in formulas

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

what is conserved in chemical reactions

A

mass charge and energy

31
Q

the law of conservation of mass

A
  • mass is neither created nor destroyed in any chemical reaction
  • the number of atoms of each element in the reactants must equal the number of atoms of each element in the products
32
Q

combustion

A

a chemical combines with OXYGEN to produce carbon dioxide and water

33
Q

synthesis

A

production of a single compound from two or more substances (elements)

34
Q

methane

A

CH4

35
Q

decomposition

A

when a single compound breaks down into 2 or more simpler substances

36
Q

single replacement

A

an element (a) reacts with a compound (bc) to take the place of one of the components of the compound

37
Q

double replacement

A

two compounds both exchange partners

38
Q

atom

A

smallest particle of an element

39
Q

atoms are made of 3 subatomic particles

A

protons, neutrons, electrons

40
Q

nucleon

A

any particle found in the nucleus (protons and neutrons)

41
Q

all atoms are electrically neutral because…

A

electrons = #protons

42
Q

protons

A
  • particles found in the nucleus of an atom
  • have a mass of 1 amu
  • each have a +1 charge
  • number of protons of an atom NEVER change
43
Q

atomic number

A

the number of protons

44
Q

nuclear charge

A

the number of protons

45
Q

neutrons

A
  • particles that are located in the nucleus
  • have a mass of 1 amu
  • neutral charge
46
Q

mass number

A

the total number of protons and neutrons in an atom (always a whole number)

mass # = P + N

47
Q

electrons

A
  • particles that rotate or revolve around the nucleus
  • very small (1/1836 of a proton)
  • mass = zero AMU
  • charge for each is -1
  • electrons are lost and gained in chemical reactions
48
Q

23
Na
11

A

23 <- mass number (P + N)
Na <- element symbol
11 <- atomic number (=P)

49
Q

S-32 , C-12

A

32 & 12 are mass numbers

50
Q

ions

A

atoms with a charge
- #Protons does not equal #Electrons
- amount of positive charge does not equal negative charge

51
Q

isotopes

A

atoms of the same element that have the same number of protons, BUT a different number of neutrons

  • named after their mass number
52
Q

atomic mass

A

average of the masses of all naturally occurring isotopes of an element

  • written as a decimal
  • closest to the mass number of the most common isotope
53
Q

john dalton

A

cannonball model
- believed that atoms were solid with indivisible parts
- atoms were indestructible
- believed that atoms are the basic unit of matter

54
Q

jj thomson

A

plum pudding model
- discovered electrons using a cathode ray tube
- believed atoms were solid, positive spheres with electrons embedded in it

55
Q

ernest rutherford

A

nuclear model
- an atom has a positive nucleus at the center, with electrons outside the nucleus
- atom is made up mostly of empty space

56
Q

gold foil experiment

A

observations:
- most alpha particles went through the gold foil
- occasionally an alpha particle was deflected back

conclusions:
- atom is made up mostly of empty space
- an atom has a positive, dense, nucleus

57
Q

niels bohr

A

planetary/bohr model
- electrons are arranged in energy levels in orbit around the nucleus
- electrons orbit around the nucleus like planets move around the sun
- electrons revolve around in several concentric rings/shells/PELs
- each ring represents an amount of energy electrons have associated with a definite average distance from the nucleus

58
Q

PEL 1 electron capacity

A

2

59
Q

PEL 2 electron capacity

A

8 electrons

60
Q

PEL 3 electron capacity

A

18 electrons

61
Q

PEL 4 electron capacity

A

32 electrons

62
Q

modern theory

A

wave mechanical theory or electron cloud model
- one cannot predict the exact position of an electron in time
- electrons are found in orbitals

63
Q

orbitals

A

regions of electron probability

64
Q

electronic configuration

A

of electrons in each ring around the atom

65
Q

valence electrons

A

electrons that are in the outermost ring of an atom, involved in bonding

66
Q

ground state

A
  • all the electrons are in the lowest energy orbitals or rings
  • this state is the electron configuration given on the periodic table
67
Q

excited state

A
  • an electron has absorbed energy and temporarily moved to a higher energy ring
  • unstable condition
68
Q

light produced

A
  • when an electron absorbs energy it jumps away from the nucleus and enters the excited state
  • when the electron falls back down to the ground state it releases energy in the form of light
69
Q

spectroscope

A

an instrument that can separate polychromatic light into the many wavelengths of light that make it up

70
Q

color spectrum of an element is

A

a unique characteristic and can be used to identify it; it’s a unique fingerprint

71
Q

sublevels

A

s p d f

72
Q

principle quantum number

A

determines the number of sublevels within the PEL

73
Q

electron spin

A

an orbital can hold only two electrons and they must have opposite spin

74
Q

electron configurations w skips

A
  • note that after the 3p sublevel is filled, the 4s is filled than the 3d
  • 4s is further from the nucleus BUT electrons in 3d have more energy due to repulsion between electrons

chemistry (11 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions