chem h units 1-8

intramolecular forces

happens within a molecule

intermolecular forces

happens between separate molecules

electronegativity in bonding

EN determines the type of intra bond

Intra Ionic bonding

e- transferred from metal to non-metal. Forms ions. Big EN difference

intra metallic bonding

valence e- are shared with all atoms and “glue” metal atoms together. between two metals

intra covalent bonding

e- are shared and orbitals overlap. Similar EN, attract and repulse is equal. Non polar and polar.

Non- polar covalent bonds

equally shared e-. often diatomic

polar covalent bonding

unequal sharing of e-.

octet rule

When atoms bond, they tend to form the noble gas configuration of ns2 np6, which is 8 valence e-

different covalent bonds in decreasing strengths

triple, double, single

different covalent bonds in decreasing lengths

single, double, triple

breaking bonds

uses nrg, endothermic

forming bonds

releases nrg, exothermic

octahedral

6 e- pairs, 6 central atom bonds, 90º angles between each pair.

trigonal bipyramidal

5 e- pairs, 5 central atom bonds, 2 axial pairs (180), 3 equatorial pairs (120)

tetrahedral

4 e- pairs, 4 central atom bonds, 109.5º between each pair

trigonal planar

3 e- pairs, 3 central atom bonds, 120º between each pair

trigonal pyramidal

same thing as trigonal planar but with a lone pair on the central atom

linear

2 e- pairs, 1-2 central atom bonds, 180º between each pair

bent

linear but with 1-2 lone pairs on the central atom

neg side in a polar covalent bond

wherever the more EN atom is is more negative

HONC bonds

H-1, O-2, N-3, C-4

HONC lone pairs

H-0, 0-2, N-1, C-0 (onch)

dispersion forces

non-polar molecules, due to random fluctuation in e-,

dispersion forces strength

depends on how many e- there are or how long the molecule is

Dipole-dipole bonding

polar molecules, caused by attraction of permanent dipoles

hydrogen bonding

polar molecules, happens when H is bonded to N, O, or F

how do IMF’s affect molecule separation

High IMF = harder to separate

solubility

Like dissolves like

how do IMF’s affect surface tension

high IMF = high surface tension

how do IMF’s affect solubility

diff substances with similar IMF’s tend to mix

how do IMF’s affect boiling point

high IMF = high boiling point

how do IMF’s affect evaporation/volatility

high IMF = high volatility

how do IMF’s affect vapor pressure

high IMF = high vapor pressure

metal properties

high MP, solids at room temp, malleable and ductile, conducts in all states, Insoluble.

network covalent bonds

covalent bonds between molecules (diamond, graphite)

network covalent properties

high MP, hard, brittle, don’t conduct, insoluble

Ionic solids properties

High MP, solid at room temp, brittle, only molten and aqueous phases conduct, many soluble in water

noble gases properties

Low BP, gas at room temp, don’t conduct, insoluble in water, soluble in non-polar solvents

molecular solids properties

low BP, could be any phase at room temp, dont conduct, most are insoluble in water but are soluble in non-polar solvents

relative atomic mass

mass of atom compared to mass of carbon 12

how to find RAM

mass x percentage, add them together

percent composition by mass

#of atoms x RAM of atom / RMM of entire molecule = % composition

Mole

RAM RMM of a substance measured out in grams

how many particles in each mole

6.02×10²³

Molar Mass

RAM or RMM in grams per mole

molarity

moles of solute / volume of solution (L)

dilution rule

M1 x V1 = M2 x V2

STP

0º celsius, 1 atm

Volume of one mole of any gas at STP

22.4 L

what does density of a gas depend on

it depends on the molar mass of the gas molecules

density conversion factor

g/L

average molar mass of N and O

29g/mol

rate of effusion (grahams law) equation

RoE of gas A / RoE of gas B = √MMB / MMA

Gas constant if P is ATM

0.0821 (L x atm / mol x k)

Gas constant if P is mmHg

62.4 (L x mmHg/mol x K)

% yield equation

experimental / theoretical x 100

excess reactant

inital - used = excess

Precipitation

2 aq ionic substances makes at least one insoluble product.

single replacement metallic

metal reacts with ionic compound. metals switch places

single replacement non-metallic

non-metallic element reacts with ionic compound. non-metals switch

combustion

substance burns in oxygen to form oxides

Hydrocarbon combustion

substance made of C and H burns to form water and CO2

decomposition

substance breaks apart into simpler substances

synthesis

simple substances combined to make complex substance

pressure formula

pressure = force/ area

how do gases move

constant random motion

what happens when 2 gas molecules collide

they have elastic collisions (nrg is not lost)

how do IMF’s affect gases

the gas particles are too far apart to attract each other

does the volume of each molecule matter

No, they are so far apart it doesn’t matter

Kinetic energy def

the energy of motion

kinetic energy equation

KE = ½ mass x velocity²

two different gases have the same KE if

they are at the same temperature

difference between real and ideal gases

real gases have volume and attract each other

when does gas behave real

low temperatures, high pressure

how do gases exert pressure

equally, in all directions, on all surfaces

how many mmHg is equal to 1 atm

760 mmHg

manometer if the mercury is higher on the gas side

pgas = patm - h

Barometer if the mercury is higher on the atm side

pgas = patm + h

how is p related # of molecules

p is directly related to # of molecules because more molecules = more collisions

how does the mass of a molecule affect pressure

it doesn’t

how does mass affect speed

heavy molecules move slower, light ones move fast

how is p related to volume

p is inversely related to volume bc less volume = more collisions

how is p related to temp

p is directly related to temp bc higher temp = more KE = more collisions

combined gas law eq

(pressure1 x volume1) / temp = (pressure2 x volume 2)/ temp

partial pressure law

P total = Pa + Pb + Pc …

Coulomb’s law

the Force of attraction (f) between 2 charged particles depends on the individual charges (q1 q2) and the distance (d) between them

Coulomb’s law equation

F=q1xq2/d squared

Electromagnetic spectrum (low nrg to high)

Radio, Micro, IR, ROYGBIV, UV, Xray, Gamma Ray

Wavelength

distance between crests of a wave

Frequency

number of waves that pass a point per second

How to find speed of light ( c)

c= wavelength x frequency

As wavelength increases, energy…

decreases

as wavelength decreases, frequency…

increases

continuous spectrums

all wavelengths present

line spectrum

only some wavelengths present

Emission Spectrums

made when elem exposed to electricity/uv light.

Emission Spectrums: what do electrons do

Electrons jump to a higher n where it is unstable. Then release nrg as photons (light) and drop down to lower level. The farther they drop down, the more nrg released, the higher nrg light produced.

Drops to n 1

Uv light