chemical bonding and structure

Question 1

What is a metallic bond? (describe the bonding between the particles)

Answer 1

Strong electrostatic forces of attraction between metal cations and delocalised electrons

Question 2

What are the particles involved in metallic bonding?

Answer 2

Positive metallic ions and a sea of delocalised valence electrons

Question 3

Does a giant metallic structure have a high or low melting/boiling point? Why?

Answer 3

High. Large amount of energy is required to overcome the strong electrostatic forces of attraction between the cations and the “sea” of delocalised electrons.

Question 4

Does a giant metallic structure conduct electricity?

Answer 4

Yes, it is a good conductor in solid and molten state. The presence of delocalised electrons act as mobile charge carriers to conduct electricity when there is a potential difference applied.

Question 5

Is a giant metallic structure soluble in a polar solvent, and a non-polar solvent?

Answer 5

Insoluble (in both non-polar and polar)

Question 6

What is another property of a giant metallic structure?

Answer 6

Ductile and malleable: since the valence electrons in the lattice do not belong to any particular metal atom, if sufficient force is applied to the metal, one layer of positive ions can slide over another without disrupting the metallic bonding.

Question 7

What is an ionic bond? (describe the bonding between the particles)

Answer 7

Strong electrostatic forces of attraction between the metal atoms and non-metal atoms

Question 8

What are the particles involved in ionic bonding?

Answer 8

Metal and non-metal atoms (name them if the question gives the chemical name of the ionic compound)

Question 9

Does a giant ionic lattice structure have a high or low melting/boiling point? Why?

Answer 9

High. Large amount of energy is required to overcome the strong electrostatic forces of attraction between oppositely charged ions.

Question 10

Does a giant ionic lattice structure conduct electricity?

Answer 10

It is a good electrical conductor in molten or aqueous state due to the presence of mobile ions as the ions are able to dissociate in water (aqueous) / large amount of energy is able to break the strong ionic bonds between ions (molten).

Question 11

What state does a giant ionic lattice structure not conduct electricity in?

Answer 11

It cannot conduct electricity in a solid state due to the absence of mobile charge carriers as ions are held in fixed positions by strong electrostatic forces of attraction in the giant ionic lattice.

Question 12

Is a giant ionic lattice structure soluble in a polar solvent, and a non-polar solvent?

Answer 12

Most ionic compounds are soluble in polar solvents (e.g. water).
They are insoluble in non-polar solvents (e.g. alcohols, petrol, etc)

Question 13

What is another property of a giant ionic lattice structure?

Answer 13

It is hard and brittle. When a force is exerted on the ionic compound, ions with similar charge from adjacent layers face each other. Repulsive forces between the similarly charged ions splits the crystal.

Question 14

What is a covalent bond? (describe the bonding between the particles in a simple molecular structure)

Answer 14

Strong electrostatic forces of attraction between shared pairs of electrons and the nuclei of both atoms.

Question 15

What are the particles involved in covalent bonding?

Answer 15

Small, discreet molecules

Question 16

Describe the intermolecular forces between the particles of a simple molecular structure.

Answer 16

Weak van der Waals’ forces of attraction between molecules.

for polar molecules: there are strong hydrogen bonds between the water/ammonia/hydrogen fluoride molecules

Question 17

Does a simple molecular structure have a high or low melting/boiling point? Why?

Answer 17

Low. Small amount of energy is required to overcome the weak intermolecular forces between molecules.
(the process of melting and boiling do not break the covalent bonds that hold the atoms together within a molecule)

Question 18

Does a simple molecular structure conduct electricity?

Answer 18

It does not conduct electricity in any state. They have no mobile ions and no delocalised electrons to act as mobile charge carriers.

Question 19

Is a simple molecular structure soluble in a polar solvent, and a non-polar solvent?

Answer 19

It is insoluble in water (polar solvent), soluble in non-polar/organic solvents

Question 20

Describe the bonding between particles in diamond. (giant molecular structure)

Answer 20

Each carbon atom is bonded tetrahedrally to four other carbon atoms by strong covalent bonds in a 3-dimensional network forming a giant molecule.

Question 21

What particles are involved in the bonding of diamond and graphite?

Answer 21

Carbon atoms

Question 22

Does a giant molecular structure have a high or low melting/boiling point? Why?

Answer 22

High. Large amount of energy is required to break the strong covalent bonds between atoms.

Question 23

Is diamond a good conductor of electricity?

Answer 23

It is a non-conductor due to the absence of mobile charge carriers, all 4 valence electrons of each carbon atom are used up as each carbon bonds tetrahedrally to 4 other carbon atoms.

Question 24

Is diamond and graphite soluble in polar and non-polar solvents?

Answer 24

Insoluble.

Question 25

Is diamond hard or soft?

Answer 25

Diamond is hard. It is difficult to break the numerous strong covalent bonds between the atoms present throughout the giant molecular structure.

Question 26

Is graphite hard or soft?

Answer 26

Graphite is soft. The layers of carbon atoms are held loosely by weak intermolecular forces of attraction. These layers of carbon atoms can slide over each other when a force is applied.

Question 27

Describe the bonding between the particles in graphite. (giant molecular structure)

Answer 27

Within each layer, each carbon atom forms strong covalent bonds with three other carbon atoms, leading to hexagonal rings of six carbon atoms that are joined together to form 2-dimensional flat layers. Weak van der Waals’ forces of attractions exists between the layers.

Question 28

Is graphite a good conductor of electricity?

Answer 28

It is a good conductor due to the presence of delocalised electrons within the layers. Each carbon bonds to 3 other atoms, leaving 1 valence electron per carbon atom.