Atomic Structure Flashcards
What is the relative mass of an electron
1/1840
What does relative atomic mass mean
The mean mass of an atom divided by 1/12 of the mean mass of carbon 12
Isotopes of the same element will…
React the same chemically
But have different physical properties
What is mass spectometry
A technique used to identify different isotopes and find the overall RAM of an element
Explain the process of Electron Impact
3 points
1)High energy electrons is sent from an electron gun
2)Passes area of high voltage where an electron is knocked off
3)Hits a negatively charged detector at the end which produces a current
Explain the process of Electron Spray Ioninisation
5 Points
1)Sample is dissolved and injected in needle to give a fine mist
2)Tip of needle is attached to the positive terminal of a high voltage power supply
3)Particles are ionised gaining an electron
4)Attracted to a negatively charged plate where they hit a detector
5)When it hits a current is made
What is Aufbau’s principle
Electrons enter the lowest energy level
What is Hund’s rule
Electrons like to occupy empty orbitals
What is the chemical
formula for electron impact
X(g) —-> X+(g) + e–
What is the formula for electrospray ionisation
X(g) + H+ —-> XH+ (g)
What is Ionisation Energy
The minimum amount of energy needed to remove one mole of electrons from one mole of atoms in a gaseous state
3 factors which affect ionisation energy
1)Distance from the nucleus
2)Nuclear charge
3)Shielding
What happens to the ionisation energy as it changes from one group to the next
decreases
What happens to ionisation energy as you go down a group
decreases
Why does ionisation energy decrease when going from 5 to 6 group
Due to the fact that phosphorus is semi stable and sulfur has unequal stability
