Atomic Structure

Where most of the mass is concentrated

Very small

Contains protons and neutrons

Make up most of the volume

orbits the nucleus in shells

+1

1

0

1

-1

1/2000

different number of protons or electrons

gained electrons to gain full outer shell and become a more stable ionic compound

lost electrons to gain a full outer shell of electrons and become more stable ionic compound

elements with the same number of protons and electrons but a different number of neutrons

sample is ionised so it can travel through TOF mass spectrometer

The sample is pushed through a nozzle making a high pressure jet. A high voltage is passed through causing the loss of an electron. A gaseous positively charged sample is produced = electrospray ionisation

The positive ions are passed through an electric field. Particles with lower mass/charge (m/z) ratio will accelerate quicker

The positive ions are passed through an electric field. Particles with a lower (m/z) ratio will accelerate quickly

Ions are detected as electrical current is made when particle hits the plate. Particles with lower m/z reach the detector first as they travel faster

the average mass of an atom of an element when measured on a scale where the mass of an atom of C12 is exactly 12

the mass of an atom of an isotope of an element is measured on a scale where the mass of C12 is exactly 12

the average mass of a molecule when measure on a scale where the mass of an atom of C12 is exactly 12

the mass of an isotope/charge

= (abundance A x m/z A) + (abundance B x m/z B) / total abundance

chromium and copper

an electron moves from the 4s orbital into the 3d orbital to create a more stable half full or full subshell respectively

the minimum amount of energy to remove 1 mole of electrons from 1 mole of atoms in the gaseous state

the more electron shells between the positive nucleus and negative electron that is beiung removed, the less energy required. There is weaker attraction.

Bigger the atom = further away the outer electrons from the nucleus. The attractive force between the nucleus and outer electrons reduces meaning it is easier to remove the electrons

the more protons in the nucleus = the bigger the attraction between the positive nucleus and the negative outer electron = more energy to remove the electron.

removal of more than 1 electron from the same atom

ionisation energy decreases as we go down the group

The atomic radius increases = the outer electrons are further away from the nucleus. the attractive force is weaker. the energy needed to remove the electron decreases

Shielding increases = more shells between the nucleus and the outer shell. the attractive force is weaker. the energy needed to remove the electron decreases.

Niels Bohrs model is correct = evidence for shells

ionisation energy increases across a period

increases nuclear attraction because there is an increasing number of protons in the nucleus

the shielding is similar and the distance from nucleus decreases

the ionisation energy increases as more energy is needed to remove an electron