Module 3

Question 1

Which group contains the alkali metals?

Answer 1

Group 1

Question 2

Which group contains the alkaline earth metals?

Answer 2

Group 2

Question 3

Which groups contain transition metals?

Answer 3

Group 3-12

Question 4

Describe how the elements are ordered in the periodic table.

Answer 4

By increasing atomic (proton) number;
In periods showing repeating trends
in physical and chemical properties
(periodicity);
In groups having similar chemical properties

Question 5

Which elements are part of the S-block?

Answer 5

Groups one and two/alkali and alkaline earth metals

Question 6

Which elements are part of the P-block?

Answer 6

Groups 13-18 (Groups 3-8/0)

Question 7

Which elements are part of the D-block?

Answer 7

Groups 3-12/transition metals

Question 8

Explain the trend in electron configuration along the periodic table

Answer 8

Each period is another energy level and each subshell is a block, with the most outer subshell being equal to the specific block. E.g an element in period two in the P-block will have be in the second energy level and have two S-subshells and one P-subshell.

Question 9

Define the first ionisation energy

Answer 9

The amount of energy required to remove one mole of electrons from one mole of a gaseous atoms

Question 10

Explain the general trend in the ionisation energy going along period two or three

Answer 10

The nuclear charge increases and, as they are in the same shell so have similar shell shielding, the nuclear attraction increases, decreasing the atomic radii, increasing the first ionisation energy

Question 11

Explain why there is a dip in ionisation energy between Beryllium and Boron/Magnesium and Aluminium

Answer 11

The 2/3p subshell has a higher energy requirement than the 2/3s subshell, therefore, is easier to remove, so has a lower ionisation energy.

Question 12

If the successive ionisation energies of Boron are 800.6 kJ/mol, 2427 kJ/mol, 3660 kJ/mol, x and 32822 kJ/mol, predict the value of x

Answer 12

Exact value: X=25025 kJ/mol

A value between 20000-30000kJ/mol will probable be accepted.

Question 13

If the successive ionisation energies of element x are 786.5 kJ/mol, 1577.1 kJ/mol, 3231.4 kJ/mol, 4355.5 kJ/mol, 16091 kJ/mol, 19784 kJ/mol, 23786 kJ/mol, etc… Predict element x

Answer 13

Silicon - must be in group four and can’t be carbon for there are seven ionisation energies shown.

Question 14

What is metallic bonding?

Answer 14

A strong electrostatic attraction between cations (positive ions) and delocalised electrons.

Question 15

What is a giant metal lattice?

Answer 15

The structure which all metals have.

Question 16

Describe metallic bonding

Answer 16

The cations are fixed in place, maintaining the structure and shape of the metal;
The delocalised electrons are mobile and able to move throughout the structure.

Question 17

Describe what makes up a metallic bond

Answer 17

Each atoms donate their negative outer-shell electrons into a shared pool ‘sea’ of delocalised electrons;
The remaining positive ions left behind are consist of the positive nucleus and inner shell electrons of the metal ion.

Question 18

Give three properties which metals generally have.

Answer 18

Strong metallic bonds;
High electrical conductivity;
High melting and boiling points.

Question 19

Describe and explain why metals have high electrical conductivity.

Answer 19

For the delocalised electrons can carry a charge and move through the metal when a voltage is induced.

Question 20

Describe and explain why metals have high melting and boiling points

Answer 20

Depends on the strength of the metallic bonds:
High temperatures are necessary to provide the large amount of energy needed to overcome the strong electrostatic attraction between the electrons and the cations, resulting in a high melting point.

Question 21

Describe the solubility of metals

Answer 21

Metals do not dissolve. Whilst it might be thought that they might interact with a polar solvent, any interaction is caused by a reaction instead.

Question 22

What is a giant covalent lattice?

Answer 22

Networks of atoms joined by strong covalent bonds.

Question 23

What are the physical properties of a giant covalent lattice?

Answer 23

Often a tetrahedral shape, with a bond angle of 109.5 degrees, as the four electrons of a group four element bond with another four elements, and so on.

Question 24

Why do giant covalent lattices have high melting points and boiling points?

Answer 24

For the strong covalent bonds require a lot of energy to be broken

Question 25

Why are giant covalent lattices insoluble in solvents?

Answer 25

For the interaction with solvents is not strong enough to break the strong covalent bonds.

Question 26

Why do giant covalent structures not conduct electricity (ignoring graphene and graphite)?

Answer 26

For all of the electrons are locked in place by strong covalent bonds.

Question 27

Why can graphene and graphite conduct electricity?

Answer 27

For they have one free electron, which can travel through the structure, carrying a charge.

Question 28

Explain the variation of melting points across periods two and three.

Answer 28

For the first three metals, generally, the melting points increase, as the metal will form a greater charge with its cation, so will have a greater attraction to the electrons. The group four element will have the highest melting point, as it will be a giant covalent lattice. The melting point then dramatically drops, as the other elements form giant molecular structures, with are only held together by weak intermolecular forces.