The nucleus is the term given to the centre of the atom comprising of the proton and neutron
Reactivity is a measure of how easily an element will combine with other elements to form compounds. Some elements are unreactive and need energy putting in others will react spontaneously and easily.
Atomic structure is the positively charged nucleus and the negatively charged electrons circling around it, within an atom.
The atomic number of the elements provides information on the number of protons in the nucleus.
Ions are atoms or groups of atoms that have either lost or gained electrons so they have a positive or negative charge.
Electrons exist in shells around the nucleus and have different configurations and layouts based on the element in the periodic table. Electrons are also very important in bonding.
Atomic radius is the measure of the distance from the centre of the nucleus to the outer electron.
The nuclear charge of an atom is the measure of the effect of attraction between the protons in the nucleus and the outer electron
Shielding is the effect of the inner shells of electrons on weakening the attraction between the protons in the nucleus and the outer electron.
Ionisation energy is a measure of the amount of energy required to remove an outer electron from an atom creating a positively charged ion.
Electrons are essential components of an element and decide its reactivity and bonding. They have their own unique properties known as quantum numbers which makes them all unique, existing in a number of sub orbitals around a nucleus.
Our understanding of the atom and nucleus and electrons that surrounds it has come a long way since Ancient Greek times to our understanding of today. With this understanding there have been big leaps in technology and theories that have disproved other theories leading to the model we have today.
The work of J.J Thomson’s student, Ernest Rutherford, led to the discovery of the Proton. Working with alpha particles fired at a piece of gold foil it was observed that instead of passing straight through it was scattered. Suggesting there was something large in the centre of the atom.
The atomic radius is a measure of the distance from the nucleus to the valence electron.
Electronegativity is a measure of the ability of an atom to attract electrons towards it in a covalent bond
Transition metals can form colored compounds when bonded to other elements due to the energy levels of the d block where electrons can be excited and move between energy levels.