Topic 1.1 Atomic structure and the periodic table Flashcards
Molecular ion peak
-The peak furthers to the right
-It is the peak with the highest mass to charge ratio (m/z)
-Whole mass of the compound before its broken down
Base peak
-The base peak is always the tallest peak in the spectrum
-It represents the most common and most abundant ion
Mass number
Sum of protons and neutrons of a particular isotope
(in the nucleus of an atom).
First ionisation energy
-The first ionisation energy is the energy required to remove the first (one) electron from each atom in one mole of atoms in the gaseous state.
log10=x ionisations energy
Inverse: 10^x=IE
Electron configuration of copper
1s2 2s2 2p6 3s2 3p6 4s1 3d10
Unstable (without a full 3d orbital)
1e- moves from 4s to 3d so there’s a full orbital in 3d and 4s which is more stable than full 4s, not full 3d.
Electron configuration of cr
1s2 2s2 2p6 3s2 3p6 4s1 3d5
Unstable (without a half full 3d orbital)
1e- moves from 4s to 3d so there’s a half full orbital in 3d and 4s which is more stable than full 4s, not full 3d.
Second ionisation energy
The energy required to remove an electron from each singly charged positive ion in one mole of positive ions in the gaseous state.
Relative atomic mass (Ar)
The weighted mean (average) mass of an atom of an element compared to 1/12 of the mass of an atom of carbon-12.
Three factors that determine the magnitude of the first ionisation energy
-The orbital in which the electron exists
-The nuclear change of the atom
-The shielding experienced by the electron from all other electrons present
Sub-shell electrons
Sub-shells: Number of electrons:
s sub-shell 2 (1x2)
p sub-shell 6 (3x2)
d sub-shell 10 (5x2)
f sub-shell 14 (7x2)
Electron configuration order
1s 2s 2p 3s 3p 4s 3d (4s is filled before 3d)
4s is less compact than 3d so e- fill it first as there is more space: e- repel each other so more space means less repulsion.
Relative isotopic mass
The mass of an individual atom of a particular isotope relative to 1/12 of the mass of carbon-12.
Quantum shell electrons
1st quantum shell: 2 (no. of electrons)
2nd quantum shell: 8
3rd quantum shell: 18
4th quantum shell: 32
First ionisation equation
Na(g) —> Na+(g) + e-
Second ionisation equation
Na+(g) —>Na^2+(g) + e-
Mass spec
-Analytical technique used to determine the molecular mass of a compound (indirectly proved the existence of isotopes)
-Only a small sample is required
-Pattern of deflection according to charge and mass is depicted on a spectrum
-Ions with a large mass to charge ratio are deflected less than ions with a smaller mass to charge ratio.
RAM calculations
Easy:
1. Work out difference in mass between isotopes
2. Work out difference between each isotope mass and RAM
3. Divide answers to 2. by 2
4. Multiply by 100
An orbital
An orbital is a region within an atom the can hold up two electrons with opposite spins- in any orbital can fit 2 electrons which fit into sub shells
s orbital- sphere shaped
p orbital- dumbbell shaped
