Master this deck with 44 terms through effective study methods.
Imported from Quizlet
Electron: mass = 0 Charge = -1 Proton: mass = 1. Charge = +1 Neutron: mass = 1. Charge = 0
The sum of the number of protons and neutrons in a nucleus of an atom.
The number of protons in a nucleus of an atom of an element.
The weighted mean mass of an atom of an element relative to 1/12th of the mass of an atom of carbon-12.
Atoms of the same element that have different numbers of neutrons but the same number of protons.
The mass of an individual atom of a particular isotope of an element relative to 1/12th of the mass of an atom of carbon-12.
Sum of (isotope abundance x isotope mass number) / (sum of abundances of all the isotopes)
an instrument used to determine the relative masses of atoms by the deflection of their ions on a magnetic field / measuring the time of flight
The average mass of an entity compared to one twelfth of the mass of an atom of carbon 12.
Observing the peak with the greatest m/z (mass : charge) ratio (aka the peak furthest to the right).
Look at the relative peak heights for each isotope. Use the Ar equation to calculate the Ar. Eg. Chlorine exists in two isotopes, 35Cl and 37Cl. The ratio is approx. 3:1 Therefore ((3x35)+(1x37)) / 4 =35.5
M/z = 35: 35Cl+ M/z = 37: 37Cl+ M/z = 70: 35Cl2+ M/z = 72: ([35Cl][37Cl])+ M/z = 74: 37Cl2+
9:6:1 - There is a 3/4 chance of chlorine existing as 35Cl. So the total chance is (3/4) x (3/4) =9/16 =0.563 -There is a 1/4 chance of chlorine existing as 37Cl. So the total chance is (1/4) x (1/4) =1/16 =0.0625 -There is a (1/4) x (3/4) chance of ([35Cl][37Cl]) existing, but we must multiply this by 2 to makeup for the other direction. Therefore the likelihood is 6/16 =0.375 Therefore the ratio is 9/16 : 6/16 : 1/16 Hence 9:6:1 This ratio should correspond to the relative sizes of molecular ion peaks.
The second furthest peak to the right
This is known as the M + 1 peak for which isotope carbon-13 is responsible for.
The volume of space where certain electrons of specific energy are restricted to move around the nucleus.
first quantum shell
division of an energy level (s,p,d,f)
A region of space within an atom that can hold up to two electrons with opposite spin.
sphere of electron density around the nucleus; lower in energy than other orbitals because electron density is closest to the nucleus
spherical
One
Two
dumbbell / figure of 8
Three
Six
Five
Ten
1s 2s 2p 3s 3p 4s 3d 4p 5s 4d 5p
2
8
18
32
1s2 2s2 2p6 3s2 3p6 4s1
The 4s orbital is lower in energy when they are both unfilled
Electrons will occupy orbitals singly before pairing takes place.
Two electrons cannot occupy the same orbital unless they have opposite spin
An electron occupies the lowest-energy orbital that can receive it
Atomic emission spectra
- Atoms in gaseous state are heated - electrons become excited and jump to higher energy levels - the electrons return to ground state (normal) - energy is emitted as electromagnetic radiation - detected using a spectroscope - each frequency of radiation emitted is specific to an element - the fact these values are fixed shows that electrons can only have certain energy levels, and not continuous
The energy required to remove one mole of electrons from one mole of gaseous atoms of an element to form one mole of gaseous 1+ ions.
X(g) —-> X+(g) + e- X+(g) —-> X2+(g) + e- X2+(g) —-> X3+(g) + e-
A measure of the energy required to remove each electron one at a time from the gaseous atom or ion to form the subsequent gaseous ion.
- within each shell, successive ionisation energies increase because electrons are being removed from an increasingly positive ion and there's less repulsion amongst remaining electrons so they're held more strongly by the nucleus - the big jumps in ionisation happen when a new shell is being broken into so an electron is being removed from a shell closer to the nucleus