Periodic table

Question 1

Valency

Answer 1

the number of electrons that an atom will gain, lose or share in order to obtain the stable noble gas electron configuration

Question 2

Octet rule

Answer 2

Atoms tend to gain, lose or share electrons in order to achieve the electron configuration of the Noble gases

Question 3

Atomic radius

Answer 3

The distance from the nucleus of an atom to the outermost shell of electrons

Question 4

Atomic radius trend

Answer 4

Decreases from left to right within a period (caused by the increase in the number of protons and electrons across a period)

Increases down a group (valence electrons occupy higher levels, so the valence electrons are further away from the nucleus)

Question 5

Ionisation energy

Answer 5

The amount of energy require to remove an electron from an atom to form a positive ion

Question 6

Ionization energy trend

Answer 6

Increases from left to right across a period because:
- increased nuclear charge (more protons in the nucleus) of the atoms as we move across a period
- decreased atomic radius (distance between the nucleus and valence electrons)

Decreases as we go down a group because:
- Valence electrons of atoms are higher energy levels, farther away from the nucleus
- means that the force of attraction between the positively charged nucleus and valence electrons is weaker, therefore making it easier to remove an electron from the atom.

Question 7

Successive ionization energies

Answer 7

Energy required to remove the first, second, third etc electron from the same atom

Question 8

Electronegativity

Answer 8

A measure of the tendency of an atom to attract a bonding pair of electrons

Question 9

Electronegativity trends

Answer 9

Increases from left to right across a period and decreases down a group

Question 10

Electronegativity calculation

Answer 10

If ionization energy and electron affinity are high = atom will also have high electronegativity

If ionization and electron affinity are low = atom having low electronegativity

Question 11

Ions

Answer 11

A small charged particle

Question 12

Positive ion

Answer 12

Cation

Question 13

Metallic character

Answer 13

Relates to the ability to lose electrons and non-metallic character relates to ability to gain electrons

Question 14

Negative ion

Answer 14

Anion

Question 15

Metallic character trends

Answer 15

Decreases from left to right across a period and increases down a group

Question 16

Electron affinity

Answer 16

Energy change that occurs when an electron is added to a neutral atom to form a negative ion