Module 3: Periodic Table And Energy

Question 1

What is the periodic table arranged by?

Answer 1

Increasing atomic numbers.

Question 2

What does a ‘Group’ on the periodic table represent?

Answer 2

Colums, the number of electrons in the outer shell of an element.

Question 3

What does a ‘Period’ on the periodic table represent

Answer 3

Rows, number of electron shells

Question 4

What is ‘first ionisation energy?’

Answer 4

The energy required to remove one electron from each atom in one mole of gaseous atoms to form one mole of gaseous 1+ ions.

Question 5

Example of First Ionisation Energy Equation:
Give the equation for the first ionisation of Hydrogen.

Answer 5

H(g) -> H+(g) + e-

Question 6

What is the ‘Second Ionisation Energy?’

Answer 6

The energy required to remove one electron from each ion within one mole gaseous, +1 ions to make one mole of gaseous +2 ions.

Question 7

Example of Second Ionisation Energy Equation:
Give the equation for the second ionisation of Helium.

Answer 7

He+1 (g) —> He+2 (g) + e-

Question 8

What are the three factors effecting Ionisation Energy and why do these have an effect?

Answer 8

• Atomic Radius: The larger the distance between the nucleus and the outer electron, the less attraction there will be.
• Electron Shielding/Repulsion: Inner shells of electrons repel outer shell electrons as they are all negatively charged, reducing the attraction.
• Nuclear Charge: The more protons in the nucleus, the stronger the attraction between outer-electrons and the nucleus will be.

Question 9

How can a ‘Successive ionisation energies’ graph provide evidence for groups/periods?

Answer 9

Between shells of electrons, there will be a large increase in ionisation energies; providing evidence for the number shells and the number of electrons in each shell.

Question 10

What would a small drop in ionisation energies across a period in a ‘Successive Ionisation energies’ graph provide evidence for?

Answer 10

While there is usually an increase in ionisation energies across a period, Small drops can be seen between groups 2-3 and 15-16, this is because a new sub-shell has been started.

Question 11

What is the trend in Ionisation Energy across a period and why?

Answer 11

Ionisation Energy increases across a period as the nuclear charge increases, atomic radius and shielding stays relatively the same.

Question 12

What is the trend in Ionisation Energy down a group and why?

Answer 12

Ionisation Energy decreases, as the atomic radius increases due to more electron shielding and nuclear charge increases.

Question 13

What is ‘Metallic Bonding?’

Answer 13

The electrostatic attraction between Metal cations and delocalised electrons.

Question 14

What is a ‘Cation?’

Answer 14

A positive ion
(Cat-ions are paw-sitive… no? okay.)

Question 15

What is an Anion?

Answer 15

A negatively charged ion.

Question 16

Describe the structure in a Giant Metallic Lattice.

Answer 16

A giant lattice of regularly arranged cations, surrounded by a sea of delocalised electrons

Question 17

What are the properties of Giant Metallic Structures? (hints: m.p. b.p., e, m, d)

Answer 17

• High melting and boiling points: Strong electrostatic attraction requires lots of energy to overcome.
• Insoluble in water.
• Conducts electricity: as electrons can freely move around, carrying electrical charges.
• Ductile (can be stretched) and Malleable (shaped): as ions can slide over each other.

Question 18

What are the properties of Diamond Giant Covalent Structures?

Answer 18

• Formed in a Tetrahedral structure with a bond angel of 109.5° (each carbon bonded 4 times, fuck off OCR.)
• Hard lattice structure.
• High m. and b.p. - strong electrostatic attraction.
• Does not conduct as there are no free, outer electrons (all in covalent bonds.)
• Insoluble, solvents can’t break bonds.

Question 19

What are the properties of Graphite Giant Covalent Structures?

Answer 19

• Trigonal Planar structure, bond angle of 120°
• Soft (as graphene layers can slide over each other)
• Can conduct (free electron not involved in bonding carries charge.)

Question 20

How can changes in m. and b.p. be explained across a period?

Answer 20

Due to changes in molecular structure and bonding.

Question 21

What are Diamond Giant Covalent Structures and Graphite Giant Covalent Structures made from?

Answer 21

Pure carbon

Question 22

What’s 9 + 10?

Answer 22

21

Question 23

What are the names of Group 0, 1 & 17 elements?

Answer 23

0: Nobel Gasses
1: Alkali Metals
17: Halogens

Question 24

What is the trend in reactivity in group 2?

Answer 24

Reactivity increases moving down the group.

Question 25

Does melting and boiling points increase or decrease down group 17 and why?

Answer 25

Increase, as an increase in electrons increases intermolecular forces.

Question 26

What happens during a Displacement Reaction?

Answer 26

A more reactive element takes the place of a less reactive element in a compound.

Question 27

Does reactivity increase or decrease down group 17?

Answer 27

Decreases as atomic radius increases and electron shielding increases.

Question 28

What is Reduction and what is Oxidation?

Answer 28

Reduction is the gain of electrons during a reaction, Oxidation is the loss of electrons.

Question 29

What is a Disproportionation Reaction?

Answer 29

A reaction in which an element is both oxidised and reduced?

Question 30

Describe the method and possible results for the test for Halide Ions.

Answer 30

Add an aqueous solution of silver nitrate to a Halide Solution and note the colour of the precipitate formed. White precipitate indicates Silver Chloride formed. Cream precipitate indicated Silver Bromide formed. Yellow Precipitate indicates Silver Iodide formed.