Periodicity

Question 1

Factors that can affect ionisation energies

Answer 1

• nuclear charge
• distance from the nucleus/ nuclear attraction
• shielding

Question 2

What can affect general trend of increasing ionisation energy.

Answer 2

• different period= new sub-shell
  Less/ more shielding
• different orbital
  Higher or lower energy orbital= more/ less energy needed
• spin pair repulsion
  Repulsive force between paired electron in orbital
  Easier to remove= less energy needed

Question 3

Describe metallic bonding

Answer 3

Strong electrostatic attraction between

• metal cations
• delocalised electrons

Question 4

What are delocalised electrons

Answer 4

Electrons shared between more than 2 atoms

Question 5

Covalent bonding

Answer 5

• electrostatic attraction
• pair of shared localised electrons
• between atom atoms bonded

Question 6

What affects the strength of metallic bond

Answer 6

• amount of d.e- = stronger

- charge on cation; greater= stronger

Question 7

Explain properties of metals

Answer 7

• High melting and boiling points;
  Strong metallic bonds
• Electrical conductors
  Delocalised electrons free to move and carry charge
• Malleable and ductile;
  Layers of same sized atoms able to slide in new positions
  W/o breaking bonds

Question 8

What are alloys and why are they not compounds?

Answer 8

• a mixture of metals
• different sized atoms increases strength of metals; disallows sliding of layer
• not a fixed ratio of mixture

Question 9

Similarities with ionic and metallic bonding

Answer 9

• strong electrostatic attraction

- giant lattices

Question 10

Differences between metallic and ionic bonding

Answer 10

• in metallic; attraction is between cation and d.e-
  Ionic; between oppositely charge ions
• in ionic; involves anions and cations
  Metallic; only cations

Question 11

Describe giant ionic lattices and examples

Answer 11

• ions formed from non- metal and metal
• regulator lattice of oppositely charge ions held by strong ionic bonds
• each ions surrounded by oppositely charged ions
• eg NaCl, CaO

Question 12

Describe giant metallic lattices and examples

Answer 12

• Metal cations bonded in lattice with d.e-; electrostatic attraction
• charge of cation and no. d.e- reflects metals group in PT
• strength of bond reflects attractive forces

Eg solid aluminium, magnesium

Question 13

Simple molecular lattices and examples.

Answer 13

• regular 3D structure of molecules
• molecules bonded by weak intermolecular forces; depending on type of molecule

Eg solid HCN N2

Question 14

Describe giant covalent lattices w/ examples

Answer 14

• 3D structure of atoms bonded by strong covalent bonds

- eg SiO2 Diamond graphite/ graphene

Question 15

Who do elements in the same group have similar properties

Answer 15

• same no of e- in putter she’ll

- as types of orbital

Question 16

Describe trend of boiling and melting point from Group 1 to 4

Answer 16

• general increase
• from Na-Al due to increased strength of metallic bonding
• from Al-Si due to covalent bond being stronger than Metalli

Question 17

Describe turned on melting and boiling point from Group 4 to 5

Answer 17

• big decrease

- from covalent bonds to induced dipole-dipole forces

Question 18

Describe trend I melting and boiling point from group 5-8

Answer 18

• decreases

- less electrons in molecules/ atoms = weaker bond in instantaneous dipole

Question 19

Define ‘first ionisation energy’

Answer 19

• energy required to remove one electron
• from each atom in a mole
• of gaseous atoms

Question 20

Periodicity

Answer 20

Repeating pattern of properties shown across different periods

Question 21

Describe the change in the first ionisation energy in different orbitals.

Answer 21

When comparing beryllium and boron for example:
The last electrons in B are in the 2p subshell
The last electrons in Be are in 2s sub-shell

2p is a higher energy level than 2s so it is easier to remove an electron from the higher energy level.

Question 22

Ionisation energy definition.

Answer 22

• The energy required to remove an electron
• From one mole of each gaseous atoms
• To form a 1+ ion.