Chem, Types of Bonds

Question 1

Metallic bonds

Answer 1

The strong electrostatic attraction between cations and the ‘sea’ of delocalised electrons.

Question 2

Metallic bonds (Good conductors of electricity)

Answer 2

Valence electrons that form the ‘sea’ of delocalised electrons. If a voltage is supplied. The electrons from the ‘sea’ of delocalised electrons will move towards a positive terminal of power supply. The cations will remain stationary in fixed positions. The movement of the valence electrons will conducts a charge.

Question 3

Metallic bonds (Good conductors of heat)

Answer 3

Electrons in the ‘sea’ of delocalised electrons are mobile, hence they are able to conduct heat in the form of (kinetic energy) through the lattice. The vibration of these particle also plays a role in flow of heat through the metal lattice.

Question 4

Metallic bonds (Malleable and ductile)

Answer 4

The bonding between cations and the ‘sea’ of delocalised electrons are known to be ‘non-directional’, therefore they cannot move in relation to each other without breaking bonds between the delocalised electrons. This allows metals to change shape.

Question 5

Metallic bonds (solid at room temperature)

Answer 5

Strong attractive forces between the cations and the ‘sea’ of delocalised electrons hold the metallic lattice together. Consequently a high room temperature is required to disrupt the lattice allowing it to melt.

Question 6

Metallic bonds (Hard)

Answer 6

Strong attraction between the cations and the ‘sea’ of delocalised electrons provide a cohesive force golding the structures together.

Question 7

Metallic bonds (Not brittle)

Answer 7

No, due to the delocalised electrons in the metallic bond allowing atoms to slide past each other without breaking bonds.

Question 8

Ionic Bonds

Answer 8

A strong electrostatic force of attraction between opposite charges.

Question 9

Ionic Bonds (Poor conductors of electricity during solid phase)

Answer 9

In an ionic solid, the ions are tightly held together in fixed positions within the lattice. thus they are unable to move and carry a charge. The absence of movement of these particles means ionic solids are unable to conduct a charge. Therefore being a poor conductor of electricity.

Question 10

Ionic Bonds (Good conductors of electricity during molten and aqueous phase)

Answer 10

In a molten or aqueous solution Ions are able to mov and carry a charge throughout the ionic fluid. The positive ion goes towards the negative electrode, and the negative ion goes towards the positive electrode. This movement of ions help conduct a charge of electricity

Question 11

Ionic (HARD AND BRITTLE)

Answer 11

If a large force is applied to an ionic structure, It can cause layers of ions to move. This forces identical charged ions to forcefully align with each other. This creates repulsion. This repulsive force exceeds that force of attraction leading for the ionic compound to break

Question 12

Ionic Bonds (High MP/BP)

Answer 12

Ionic bonds have strong electrostatic forces between ions, this results to the lattice keeping individual ions in fixed positions. Thus a high temperature is needed to break or overcome the ionic lattice.

Question 13

Ionic Bonds (poor heat conductors)

Answer 13

Poor heat conductors in a solid state due to the rigid lattice structure restricting ion movement.

Question 14

Examples of Ionic bonds

Answer 14

(NACL) (KI) (NAOH) (CSCL) (MGO) (MHOH)

Question 15

Covalent molecular

Answer 15

Strong electrostatic attraction between the positive nucleus and shared electrons in a molecule

Question 16

Covalent molecular (non conductors of electricity in all phases)

Answer 16

Due to the electrons in a covalent bond being localised in an atom. None of these electrons are able to move independently. Making the absence of mobile charged particles.

THEY DO NOT CONTAIN IONS

Question 17

Covalent molecular (Some conductors of electricity)

Answer 17

When a Covalent molecular substance mixes with water or an aqueous solution it is known to be ionised. This will make the electrons delocalised and able to move. This mobility will allow the network to conduct electricity.

Question 18

Covalent molecular (Soft and Weak)

Answer 18

Covalent molecules have strong intramolecular forces between the atoms in between molecules. However they have weak intermolecular forces of attraction between neighbouring molecules. Molecules are separated easily from one another.

Question 19

Covalent molecular (Low m.p/b.p)

Answer 19

When a substance heats or boils, week intermolecular forces are overcome and broken. Weak bonds in the lattice of a covalent bonds in solid phase are easily broken by heat melting/boiling into liquid or gas.

Question 20

Covalent molecular (Brittle)

Answer 20

Yes in solid form

Question 21

Covalent molecular (lusturous)

Answer 21

No, typically composed of non-metals.

Question 22

Covalent network

Answer 22

The strong electrostatic force of attraction between positive charged nucleus and shared electrons throughout the structure.

Question 23

Covalent network (Non conductors of heat)

Answer 23

Electrons in these substances are held in fixed positions between the atom’s shells/ covalent bonds. These electrons are unable to freely move therefore unable to conduct a charge

Question 24

Covalent network (Very hard and brittle)

Answer 24

Strong bonds occur between all atoms within a covalent molecule structure. This continuous array of strongly bonded atoms are difficult to distrust.

Question 25

Covalent network (high m.p/b.p)

Answer 25

Strong bonds occur between all atoms within a covalent network structure. A very high temperature (high particles of kinetic energy) is needed to disrupt this continuous array of strongly bonded atoms.

Question 26

Allotropes

Answer 26

Same element but different structural arrangements. For examples, Diamond and graphite are allotropes of carbon

Question 27

Diamond

Answer 27

- 3d lattice structure - each carbon atom is bonded to 4 other carbon atoms (no delocalised electrons) - no layers (no 'weaker' forces) - cannot conduct electricity. - Hard because atoms are joined by a 3D lattice structure. - Can be used in Jewellery and drilling tool bits.

Question 28

Graphite

Answer 28

- 2-D layered structure - Strong intramolecular forces in between carbon atoms - Weak intermolecular forces in between layers. Can conduct electricity - each atoms are bonded to 3 other carbons atoms, leaving one atom to be delocalised. - It has layers (soft) - used as lubricant as layers slide instead of breaking.

Question 29

Nanomaterial

Answer 29

Nano-materials are substances that contain particles in the size range 1-100 nm and have specific properties relating to the size of these particles which may differ from those of the bulk material.

Question 30

Nano Meter size

Answer 30

10 ^ -9 m

Question 31

NanoParticles

Answer 31

Spherical particles with the diameter of 1- 100 Nanometers.

Question 32

Issues with nanoparticles

Answer 32

Possible health/environmental risks, as nanoparticles are small enough to travel through skin into the bloodstream and into cells (may interact with biomolecules to form unwanted chem. Reactions) (Not enough longitudinal studies to know the adverse health side effects from nanoparticle uses. E.g. sunscreens)

Question 33

Advantages of nanoparticles in sunscreen

Answer 33

Better stability and enhanced UV protection

Question 34

Bulk materials

Answer 34

Bulk materials are particles whose size exceeds 100 nm in all dimensions.

Question 35

How do nanoparticles differ from allotropes

Answer 35

Allotropes are different structural forms of the same element. Nanoparticles, on the other hand, are materials with dimensions in the nanoscale, typically between 1 and 100 nanometers.

Question 36

Ionic solid

Answer 36

Salts that stay in a solid state that are composed of ions

Question 37

Ionic Liquid

Answer 37

Salts that stay in liquid state that are composed of ions