Atomic and Electron structure

Relative Atomic Mass

The weighted mean mass of an atom compared with 1/12th mass of an atom of carbon-12

Calculating R.A.M

Rearranging R.A.M Calculations

Isotopes

Atoms of the same element with the same number of protons but different number of neutrons

An atomic orbital

A region within an atom that can hold up to two electrons with opposite spins

S and P Orbitals

• S Orbital - Spherical

• P Orbital - Dumbbell

Electron configurations

1s²2s²2p⁶3s²3p⁶4s²3d¹⁰4p⁶5s²

Noble Gas configuration

A short hand configuration that can be written using the electronic configurations of the noble gases that come before the element

Configuration exceptions and reasons

• Chromium - 1s²2s²2p⁶3s²3p⁶4s¹3d⁵

• Copper - 1s²2s²2p⁶3s²3p⁶4s¹3d¹⁰

  Reason: They represent more stable arrangements

Electron shells and the amount of electrons in them

Describing energies between s and p orbitals

• P - orbitals have greater energy than s - orbitals

• P - orbitals have equal energy

Two differences between isotopes of the same element

• Different physical properties

• Different number of neutrons