Chemistry Note Cards - Midterm #1

produced by atoms resulted from e- moving between energy levels

charged species obbtained from atoms or molecules by adding or subtracting electrons

cations: + charged ions

anions: - charged ions

fundamental si unit that measures the "amoutns of substances"

the amount of a substance that contains as many elementary particles as there are atoms in exactly 12g of carbon

the mass of any mole of an element is equal to its atomic mass in grams

1 mole of carbons-12= 12g

can be a wave or a stream of particles (photons)

atoms of having electrons ina circular orbit around a central nucleus

only certain orbits permitted electrons can be in specific energy levels

defines energy level and size of orbitals

positive integer

as n increases, the energy of the orbial increases and the orbital size increases

collection of orbitals with the same n value

each shell can habe a maximum of n-squared orbitals

defines the three dimentional shapes of orbitals

0 to n-1

e.x. n=2 then l=0,1

defines the spatial 3-d orientation of the orbitals to respect to a standard corrdinate axis

l to -l

sheme for understanding electron configurations of the ground states of atoms

involves filling subshells in a specific order

net charge felt by outter shel electrons

z_eff=z_actual - actual shielding

z_eff is an outcome of the shape (electron density) of orbitals within a shell

upward spin (+1/2); downward spin (-1/2)

the spinning electrons can create opposity magnetic fields

there are 5d orbitals per shell b/c when L=2 there are five possible values

four of the d orbitals have a clover leaf shape with four loves and two nodal planes

the other d orbital is a cross

dumbbell shape - electron density is located on either dumbbell

node in nucleus

3P orbitals because when L=1, there are three posssible values

sphere shape

electrons are more likely to be near nucleus and decrease the farther you leave from the nucleus

as the size increases, the value of n increases

sign for an orbitals (an allowed engery state of an electron)

results from a matchmatical (wave) equations that describe the allowed energy states of electrons

"rare earth metals"

have completely filled 4f subshells and readily give rise to cations that have incompletely filled 4f subshells

last row of elements (starts at Z=90)

have not been found in nature but have been synthesized

group 8A

are shown in brackets that most nearly precedes the element being considered

helps with e- configuration b/c it saves time by not having to write out entire e- configuration but can just start at the nearest noble gas (short hand)