C3- Structure & Bonding

Question 1

States of Matter: MELTING/BOILING & FREEZING/ CONDENSING: Energy

Answer 1

• Melting/ Boiling: energy from surroundings to substance

- Freezing/Condensing: energy from substance to surroundings

Question 2

States of Matter: LIMITATIONS OF MODELS

Answer 2

• atoms molecules and ions are not solid spheres with no forces between them

Question 3

Atoms to Ions: REACTING ELEMENTS

Answer 3

Elements react to form compounds be gaining/ losing electrons or sharing electrons

Question 4

Giant Iconic Structures: SOLID

Answer 4

• fixed in position in giant lattice
• vibrate but can’t move around
• don’t conduct electricity

Question 5

Giant Ionic Structures: MOLTEN IONIC COMPOUNDS

Answer 5

• high temps provide enough energy to overcome strong attractive force
• ions green to move within molten compound
• doesn’t conduct electricity

Question 6

Giant Ionic Structures: IONIC COMPOUND SOLUTION

Answer 6

• water molecules separate ions from lattice
• ions free to move within solution
• does conduct electricity

Question 7

Giant Ionic Structures: MELTING POINTS

Answer 7

• high

— as it take lots of energy to break strong ionic bonds that hold ionic lattice together

Question 8

Covalent Bonding: BETWEEN?

Answer 8

Between atoms of non-metals share pairs of electrons

Question 9

Simple Molecule Structure: PROPERTIES

Answer 9

• low melting and boiling points
• forces between them are weak (link to melt&boil point)
• no overall charge so can’t carry electrical charge

Question 10

Giant Covalent Structures: PROPERTIES

Answer 10

• very high melting and boiling points
• insoluble in water
• hard and don’t conduct electricity (not graphite)

Question 11

Giant Covalent Structures: DIAMOND

Answer 11

• rigid structure so make is very hard

Question 12

Giant Covalent Structures: GRAPHITE

Answer 12

Giant layers with no bonding between layers- so can slide over each other
- Have free electrons- so can conduct electricity and heat

Question 13

Fullerenes: STRUCTURE (2)

Answer 13

• forms of carbon

- form large cage-like structures & tubes

Question 14

Fullerenes: USES (3)

Answer 14

• transport mechanism for drugs to specific sites in body
• catalysts
• reinforcement for composite materials

Question 15

Graphene: STRUCTURE (2)

Answer 15

• single layer of graphite

- one atom thick

Question 16

Graphene: PROPERTIES (4)

Answer 16

• excellent electrical conductivity
• excellent conductor
• low density
• most reactive form of carbon

Question 17

Graphene: USES (2)

Answer 17

• more powerful computer chips

- inflexible electronic displays

Question 18

Metallic Bonding: STRUCTURE (2)

Answer 18

• built up later by layer

- regular pattern

Question 19

Metallic Bonding: HOW IT WORKS (3)

Answer 19

• positively charged ions
• held together by electrons from outermost shell of each metal atom
• these delocalised atoms move throughout giant metallic lattice

Question 20

Giant Metallic Structures: ALLOYS (2)

Answer 20

• mixture of 2+ elements with at least one of them being a metal
• harder than pure metals because regular layers are distorted by atoms of different sizes

Question 21

Giant Metallic Structures: DELOCALISED ELECTRONS (1)

Answer 21

• enable electricity and thermal energy to be transferred through a metal easily

Question 22

Nanoparticles

Answer 22

• Study of small particles between 1-100 nanometres in size

Question 23

Nanoparticles: PROPERTIES (2)

Answer 23

• have high SA:V ratio

- high percentage of atoms exposed at surface

Question 24

Nanoparticles: USES

Answer 24

• May result in smaller quantities of materials being needed as catalysts

Question 25

Nanoparticles: APPLICATIONS

Answer 25

• Glass coated in nanotech so when sun shines on triggers reaction that breaks down dirt on window
• Modern sunscreens
• Face creams & Deodorants

Question 26

Nanoparticules: DANGERS?

Answer 26

• need more research into possible issues that may arise in terms of health and the environment