exam 1 Flashcards
(23 cards)
The Avg atomic mass of an atom is determined by:
Taking a weighted average off all stable isotopic masses
In the isotope Hg^203 how many neutrons are present
123 (203-80)
As an electron moves closer to the nucleus, energy is:
released
what is the equation to find frequency of a photon
Either
1- v=c/λ
2- v=E/nh
what is the equation to find wavelength?
λ=c/v
equation to find the # of photons
n=eλ/hc
The pattern of characteristic wavelengths of light absorbed by and emitted from an atom is known as the atoms:
Atomic spectrum
when finding the mass of one mole of an element/compound what is the unit used?
g/mol
why in the atomic spectrum of hydrogen does 4.10210^-7 m have higher energy per proton than 6.56510^-7 m?
because in the equation E=h(c/λ)
E and λ have an inverse relationship
as λ goes down- E goes up
An empirical formula is…
simplest ratio of elements in a compound
Atomic # equals what in an element
of protons
in neutral atoms (p+=?)
(p+=e-)
If you change…
1- # of neutrons—>
2- # of protons —>
3- # of electrons —>
1-isotope of the element (mass# changes)
2- different element
3- ion of the element
How do you find the # of neutrons in an element?
Mass # - Atomic #
What is the nuclear charge based off of?
the # of protons
What is the sig fig rule to addition and subtraction?
least # of decimal places
What is the sig fig rule to division and multiplication?
least # of sig figs
What are the l values for orbitals s,p,d,f in that order
0,1,2,3
if l=1 what are the ml values?
-1,0,-1
how many electrons fit into the orbitals s,p,d,f in that order
2,6,10,14
1 mol of any element = what number?
Avogadro’s number
6.022*10^23 atoms or molecules
The total mass of an element/compound in grams = what number?
1 mol of that element/compound
the valence e- is found by…
finding the group (column) that the element is from
1-8
