atomic structure (physical) Flashcards
what is atomic number
number of protons
what is mass number
total protons and neutrons
what is an isotope
the same element with the same protons and electrons but with a different amount of neutrons
what are the 3 types of hydrogen
hydrogen
deuterium
tritium
what is mass spectrometer
francis aston found 2 isotopes of neon with mass numbers of 20 and 22.
Any substance that can be vapourised without decomposing can be analysed in the same way by mass spectrometry
how does the time of flight spectrometer work
accelerates an ionised sample and calculates mass per charge based on how long each object is in flight for
what are the 2 types of ionisation
electrospray and electron impact
what is electrospray
sample gains a H+ ion (mass increases by 1)
uses high voltage
what is electron impact
sample uses an electron (mass stays the same)
fires e- at sample
what is fragmentation
when a molecule passes through the mass spectrometer, it is broken into fragments which form ions and are detected
what is quantum theory
electrons are only stable when they have a particular multiple of energy (corresponds to the shells)
Shells are numbered with a principle quantum number (corresponds to period level)
what is an orbital
region where you are most likely to find an electron around a nucleus.
Energy levels of principle quantum numbers are subdivided into orbitals.
There are 4 different orbitals (subshells)
how many orbitals does S have
1
how many orbitals does P have
3
How many orbitals does D have
5
how do orbitals fill up
1s, 2s, 2p, 3s, 3p, 4s, 3d, 4p
what is pauli exclusion principle
any individual orbital can hold a maximum of 2 electrons.
electrons can repel eachother so each electron spins in the opposite direction to the other when in the orbital- reduces the effect of repulsion.
first electron is clockwise
what is Hunds rule
electrons will occupy orbitals singly where possible.
when the same orbitals are all full, electrons will spin pair
how does chromium fill
1 electron goes to 4s and the other goes to 3d because 5 single electrons in each orbital is more stable
how does copper fill
1 electron in 4s allowing 10 to go into d orbitals and giving a stable pair in each d orbital
what happens when a transition metal loses electrons in terms of orbitals
they lose 4s electrons first
what is the general equation for first ionisation
X(g) -> X+(g) + e-
what is the general equation for 2nd ionisation
X+(g) -> X2+(g) + e-
general equation for 3rd ionisation
X2+(g) -> X3+(g) +e-
why do noble gases have a higher first ionisation energy
more stable and require more energy
why do group 1 have lower first ionisation energy
they only need to lose 1 electron to gain a full shell
Why does group 3 have a slightly higher first ionisation energy than group 1 but still low
require less energy to lose outermost electron in p subshell.
p subshell is further from the nucleus and slightly shielded by s electrons
whats the general trend for 1st IE across a period
more protons/ nuclear charge increases.
outer electrons filling same shell so the same amount of shielding
greater force of attraction between nucleus and outer electrons
whats the general trends for 1st IE down a group
increases in shielding
increases in number of protons
increases in distance of the outer electrons
less attraction between outer electrons and the nucleus
