Who came up with the atomic theory and who did he say “taught” him? (maybe made him up to avert blame)
What is the law of conservation of mass?
before and after are different combination but nothing has changed
mass before = mass after
What is the law of definite composition?
the ratio of things (elements) when broken down are always the same
What is the law of multiple proportions?
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?
plum pudding model
- sphere with positive charge
- electrons in it
What was the gold foil experiment?
(Hans Geiger, Ernest Marsden)
believed nucleus was entirely positively charges
What does todays atomic theory say?
Atoms = small and fast (cloud)
unit for atomic mass
u = amu = da
symbol for atomic number
symbol for mass number
Whats the superscript on the right?
Whats the superscript on the left?
atomic mass if a group
Whats the subscript on the left?
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?
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
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 =
Atomic mass unit
Da - dalton, amu
fathers of the periodic table?
Julius lothar meyer
Name the groups…
G 17 (7a)
G 18 (8A)
Alkali earth metals
referred to by the name of the first element in the group
What are most of the elements in the periodic table?
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?
mp = -39 degrees c
mp = 3400 degrees c
Chemical reactivity of metals?
- Au, Pt very unreactive
- Na, K very reactive
How many elements are nonmetals?
Where on periodic table/
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?
What is the one liquid nonmetal?
What category does it also fall into?
What are the types of nonmetal gases and what do they exist as ?
- dont exist as molecule
- only exist as molecule
what are the monoatomic nonmetal 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?
Properties of nonmetals
brittle - pulverized when struck
insulators - nonconductor of heat and electricity
Chemical reactivity of nonmetals?
- noble gases
- F2 (most reactive)
What do nonmetals react with and what bonds do they form?
How many elements are metalloids?
Where on periodic table/
diagonal line between metals and nonmetals
Which elements are the metalloids?
B Si Ge As Sb Te Po At
Properties of metalloids?
- conduct electricity but not as well as metals
- Silicon (Si) and Germanium (Ge)
What are the types of bonding?
How are they bonded?
metal and nonmetal
electron pooling (happy to go where it is best)
What is a cation?
+ charged ion
formed from metals
atoms lose e-
What is an anion?
- charged ion
formed from nonmetals
atoms gain e-
E (alpha/proportional) : [(q1)(q2)] / r
E = potential energy q = charge r = distance
What do parenthesis mean?
there are multiple of that thing
what is the dots used in?
What are square brackets used for?
Where are they used usually?
repeating units as a whole thing
A unit of atoms that stay together as a charged unit?
Two types of chemical formula?
What formula notates the entirety of the chemical composition?
What formula is a simplified formula that provides relative ratio of elements?
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?
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?
add prefix for # of atoms (first and second element)
add the suffix -ide
don’t add mono to first element ever
Ochem = carbon-containing molecules Inochem = metal-containing molecules
Units of covalently bonded atoms that appear in various molecules giving them a specific function?
what do structural formulas show?
chemical bonds represented by?
how many atoms are attached
Ball and stick model
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!!!