chem 105 exam 1 notes by quizlet user

Intensive properties

do not depend on the amount of matter present

Extensive properties

depend on the amount of matter that is present

chemical reactions

alter the chemical makeup of a substance

Law of Multiple Proportions (Dalton)

If two elements A and B combine to form more than one compound, the masses of B that can combine with a given mass of A are in the ratio of small whole numbers.

Law of Definite Proportions (Proust)

a chemical compound contains the same elements in exactly the same proportions by mass regardless of the size of the sample or source of the compound

Avogadro's number

6.022 x 10^23. The number of particles in exactly one mole of a pure substance

G

10^9

M

10^6

k

1000

h

100

da

10

d

10

c

100

m

1000

μ

10^6

n

10^9

p

10^12

f

10^15

Boyle

Sceptical Chymist; theories should be based on observations and demonstrations; the beginning of modern science and modern view of elements

Lavoisier

Law of conservation of mass; disproved phlogiston theory

Proust

Law of definite proportions; careful measurement of mass

Dalton

Law of multiple proportions; atomic theory, elements must be composed of atoms

Thompson

cathode ray tube, discovery of the electron; plum pudding model; atoms contain positive and negative charges

Millikan

Oil drop experiment; negative charge is quantized; electrons

Curie

radioactivity; elements are composed of smaller pieces

Rutherford

gold foil experiment; positively charged nucleus; nuclear model of the atom

Plank

quantization of energy, solved the ultraviolet catastrophe

Einstein

light is quantized in photons

Bohr

line spectra, emission/absorption; quantization of angular momentum; Bohr (planetary) model

DeBroglie

matter has wavelike properties; wave/particle duality of electrons

Schrödinger

wave function of electrons; electron orbitals; modern atomic model

Mass number (a)

number of protons and neutrons

atomic number (z)

number of protons

visible light

400-750 nm

Raging Martians Invaded Venus Using X-ray Guns

radio, microwaves, infrared, visible, ultraviolet, x-ray, gamma (low to high)

effective nuclear charge (Zeff)

the actual nuclear charge experienced by an electron, defined as the charge of the nucleus plus the charge of the shielding (core) electrons; the ability of a nucleus to bind e-

Ionization energy

The amount of energy required to remove an electron from an atom

Electron affinity

the energy change that occurs when an electron is acquired by a neutral atom

Isoelectronic

same electron configuration

Coulomb's Law

electric force between charged objects depends on the distance between the objects and the magnitude of the charges

molar mass

the mass of one mole of a substance in grams

low frequency visible light

red

high frequency visible light

violet

photoelectric effect

The emission of electrons from a metal when light shines on the metal

Energy of a photon

h x frequency (E=hv)

Photon

a particle of light

E =

-hcRH(1/nf - 1/ni)

Emission/Absorption lines

result from transitions between orbitals

size of an atom =

wavelength of an electron

Heisenberg uncertainty principle

it is impossible to know exactly both the velocity and the position of a particle at the same time

Schrodinger equation; Psi^2 =

probability density

orbital

where an electron may be found 90% of the time

Schrodinger equation; Psi =

allowed energy state of an electron; uncertainty in time and location

Pauli Exclusion Principle

no two electrons in the same atom can have the same set of four quantum numbers

Planar node

L

Radial node

n-L-1

S orbital

2 electrons, 1 orbital

P orbital

6 electrons, 3 orbitals

D orbital

10 electrons, 5 orbitals

F orbital

14 electrons, 7 orbitals

electrostatic attraction

the force of attraction between opposite electric charges; lowers energy of atom

electrostatic repulsion

A force between two electrical charges that have the same sign, which pushes them apart; raises energy of atom

Electron density

electrons in larger orbitals are repelled by electrons in smaller orbitals

Effective nuclear charge

electrons are attracted to the nucleus (+/-) and repelled by other electrons (-/-)

ionization energy and electron affinity

same periodic trends (opposite of atomic radius trends)

high n value

higher energy; farther from the nucleus; electrons are removed from the higher n level