Who came up with the atomic theory and who did he say “taught” him? (maybe made him up to avert blame)
Democritus
Leucippus
What is the law of conservation of mass?
1789
Antoine Lavoisier
before and after are different combination but nothing has changed
mass before = mass after
What is the law of definite composition?
1806
Joseph Proust
the ratio of things (elements) when broken down are always the same
What is the law of multiple proportions?
1808
John Dalton
You can’t have halves or fraction ratios so there is something that cannot be broken down further
What is Dalton’s Atomic Theory?
- All matter consists of atoms: indivisible particles that cannot be created nor destroyed
- Atoms of one element CANNOT be converted into atoms of another
- Atoms of one element are identical in mass and properties that are different from atoms of other elements
- Compounds result from a combination of a specific ratio of atoms from different elements
What were two experiments to try to figure out where static electricity comes from and the relationship between matter and charge?
Cathode Ray Experiment
Gold Foil Experiment
What was the cathode ray experiment?
1897
JJ Thompson
plum pudding model
- sphere with positive charge
- electrons in it
What was the gold foil experiment?
1909
Ernest Rutherford
(Hans Geiger, Ernest Marsden)
believed nucleus was entirely positively charges
What does todays atomic theory say?
Atoms = small and fast (cloud)
electron: e-
protons: p+
neutrons: n0
unit for atomic mass
u = amu = da
symbol for atomic number
Z
symbol for mass number
A
Whats the superscript on the right?
charge
Whats the superscript on the left?
mass number
atomic mass if a group
Whats the subscript on the left?
atomic number
what does no charge mean?
protons = electrons
How do you find the number of neutrons?
mass number - atomic number
A - Z
What is the atomic number?
of protons
What is the mass number?
of protons + # of nuetrons
What are isotopes of an element?
Atoms with the same number of protons but different number of neutrons
Are chemical properties the same in isotopes?
yes, even tho they have different atomic mass
symbol for atomic mass
M
What is atomic mass?
average mass for all isotopes
Finding atomic mass=
M= (mass of isotope #1)(abundance as decimal) + (mass of isotope #2)(abundance as decimal) +…..
1 u =
1.66054x10^-24
(1/12) ^12C
Atomic mass unit
u
Da - dalton, amu
fathers of the periodic table?
Dmitri mendeleev
Julius lothar meyer
Horizontal rows?
periods
Vertical rows?
groups
Name the groups…
G 1
G 2
G 17 (7a)
G 18 (8A)
other groups
Alkali metals
Alkali earth metals
halogens
noble gases
referred to by the name of the first element in the group
What are most of the elements in the periodic table?
metals
Properties of metals
metallic luster - shine or reflect light
malleable - can be hammered or rolled into thin sheets
ductile - can be drawn into wire
hardness - resistance to change
conduct heat and electricity
Phases of metals?
solids at room temp (25 degrees c)
melting point > 25 degrees c
What is the lowest and highest melting point for a metal?
lowest:
Hg
Mercury
mp = -39 degrees c
highest:
W
Tungsten
mp = 3400 degrees c
Chemical reactivity of metals?
varies greatly
- Au, Pt very unreactive
Gold, Platinum - Na, K very reactive
Sodium, Potassium
How many elements are nonmetals?
Where on periodic table/
17 elements
upper right corner
What do nonmetals mostly consist of?
more molecules and not single atoms
What state are most, some, and one of the nonmetals?
gases
solid
one liquid
What is the one liquid nonmetal?
What category does it also fall into?
Br2
diatomic
What are the types of nonmetal gases and what do they exist as ?
monoatomic (noble)
- dont exist as molecule
diatomic
- only exist as molecule
what are the monoatomic nonmetal gases?
noble gases
what are the diatomic nonmetal gases?
H2 N2 O2 F2 Cl2
what are the solid nonmetals?
C (infinity) P 4 S 8 Se 8 I 2
What are three forms of carbon?
graphite
coal
diamond
Properties of nonmetals
brittle - pulverized when struck
insulators - nonconductor of heat and electricity
Chemical reactivity of nonmetals?
some inert
- noble gases
some reactive
- F2 (most reactive)
- O2
- H2
What do nonmetals react with and what bonds do they form?
metals
ionic compounds
How many elements are metalloids?
Where on periodic table/
8 elements
diagonal line between metals and nonmetals
Which elements are the metalloids?
B Si Ge As Sb Te Po At
Properties of metalloids?
metallic shine
brittle
semi conductors
- conduct electricity but not as well as metals
- Silicon (Si) and Germanium (Ge)
What are the types of bonding?
How are they bonded?
ionic bonds
electron transfer
metal and nonmetal
covalent bonds
electron sharing
nonmetals
metallic bonds
electron pooling (happy to go where it is best)
metals
What is a cation?
+ charged ion
formed from metals
atoms lose e-
What is an anion?
- charged ion
formed from nonmetals
atoms gain e-
Coulombs Law…
def equation
explain
opposites attract
E (alpha/proportional) : [(q1)(q2)] / r
E = potential energy q = charge r = distance
> distance
denominator grows
What do parenthesis mean?
there are multiple of that thing
what is the dots used in?
hydrates
What are square brackets used for?
Where are they used usually?
repeating units as a whole thing
polymers
A unit of atoms that stay together as a charged unit?
polyatomic atoms
Two types of chemical formula?
molecular formula
empirical formula
What formula notates the entirety of the chemical composition?
molecular formula
What formula is a simplified formula that provides relative ratio of elements?
empirical formula
Rules for writing ionic formulas
- cation given first in the formula
- subscripts formula must produce electrically neutral formula unit
- subscripts lowest whole number
- charges on ions not included in finished formula
How do u list ionic names?
anion goes second
cation name, anion with suffix -ide
How do you name ionic bonds with transition metals?
element (roman numeral), anion suffix -ide
Naming Polyatomic Oxyanions (series of 2)
less O = suffix - ite
more O = suffix - ate
Naming Polyatomic Oxyanions (series of 4)
less O = prefix -hypo / suffix -ite
More O = suffix -ite
Even More O = suffix -ate
more O = prefix -hypo / suffix -ate
How to name hydrates
name ionic compound + (prefix)hydrate
prefixes for hydrates
1 = mono 2 = di 3 = tri 4 = tetra 5 = penta 6 = hexa 7 = hepta 8 = octa 9 = nona 10 = deca
Covalent = what elements?
2 nonmetals
What element come first when naming covalent bonds?
lower group #
and then, highest period (bottom of periodic table)
Halogen+Oxygen = Halogen first
Steps to name Covalent bonds?
keep root
add prefix for # of atoms (first and second element)
add the suffix -ide
don’t add mono to first element ever
Organic chemistry
inorganic chemistry
Ochem = carbon-containing molecules Inochem = metal-containing molecules
Units of covalently bonded atoms that appear in various molecules giving them a specific function?
functional groups
what do structural formulas show?
chemical bonds represented by?
how many atoms are attached
lines
Ball and stick model
Spheres =
Sticks =
Spheres = atoms Sticks = bonds
What model is most accurate in shape and shows relative size of atom?
space filling molecule
How do chemists draw 3D?
single line = line in plane
dotted line = line going away
bolded wedge line = line coming towards you
Study the pic of molecule colors and sizes…
HELP IMA FAIL!!!
