Topic 1: Atoms & Elements, Periodic Table

Question 1

Ionization Energy

Answer 1

In physics and chemistry, ionization energy or ionisation energy, denoted Eᵢ, is the minimum amount of energy required to remove the most loosely bound electron, the valence electron, of an isolated neutral gaseous atom or molecule to form a cation.
There is no difference between ionisation energy and first ionisation energy.

Question 2

Electronegativity

Answer 2

Electronegativity, symbol χ, is a chemical property that describes the tendency of an atom to attract a shared pair of electrons towards itself. An atom’s electronegativity is affected by both its atomic number and the distance at which its valence electrons reside from the charged nucleus.

Question 3

Core charge

Answer 3

Core charge is the effective nuclear charge experienced by an outer shell electron. In other words, core charge is an expression of the attractive force experienced by the valence electrons to the core of an atom which takes into account the shielding effect of core electrons.

Question 4

Successive ionisation energy

Answer 4

Successive ionisation energy is just the progressive removal of electrons for an atom, ie removing the first electron (1st IE), followed by removing the second electron (2nd IE), followed by removing the third electron (3rd IE), and so on.

In general successive ionisation energies always increase as the electrons to be removed get closer to the nucleus, there is a strong attraction between nucleus and electron, therefore more energy is required to remove the next electron.

Question 5

Metallic Character

Answer 5

Metallic characterrefers to the level of reactivity of a metal. Metals tend to lose electrons in chemical reactions, as indicated by their low ionization energies. Within a compound, metal atoms have relatively low attraction for electrons, as indicated by their low electronegativities.

Question 6

Atomic radius

Answer 6

Atomic radius is a measurement used for the size of atoms. It can be regarded as the distance from the nucleus to the valence shell electrons.