C3

Question 0

What does nano chemistry deal with?

Answer 0

• Materials on an atomic scale

Question 1

What are nanotubes used for?

Answer 1

• Reinforce graphite tennis racquets because of their strength
• make connections and semi conductors in circuits
• Develop more efficient industrial catalysts

Question 2

Describe Buckminster Fullerene?

Answer 2

• Made of 60 carbon atoms arranges in a football like sphere
• Black solid
• Buckyball

Question 3

Describe graphite?

Answer 3

• strong covalent bonds
• Layers held together by weak intermolecular forces
• Free electrons
• High melting point as it has strong covalent bonds to break.
• need a a lot of energy to break

Question 4

What are the characteristics of Graphite?

Answer 4

• layered structure
• insoluble in Water
• black and slippery
• lustrous and opaque
• conducts electricity and has a high melting point, used to make electrodes
• giant molecular structure

Question 5

What are the characteristics of diamond?

Answer 5

• rigid structure
• insoluble in water and doesn’t conduct electricity
• used in jewellery
• used in cutting tools and it is hard and has a high melting point
• has a giant molecular structure

Question 6

Describe diamonds?

Answer 6

• made of carbon atoms bonded to four other carbon atoms by strong covalent bonds
• doesn’t have any free electrons so it doesn’t conduct electricity
• high melting point because of covalent bonds (large number) they need a lot of energy to break

Question 7

What are allotropes?

Answer 7

• different forms of the same element with atoms arranged in different structures

Question 8

What are the three types of carbon?

Answer 8

• Diamond
• Graphite
• Buckminster Fullerene

Question 9

What can be used to test the purity of a chemical?

Answer 9

• Thin Layer Chromatography (TLC)

Question 10

Plants can be extracted for medicines by?

Answer 10

• Crushing
• Boiling and dissolving
• Chromatography

Question 11

Describe the continuous process?

Answer 11

• Reactants are continually fed onto the reactor as the products are removed

Question 12

What can the continuous process do?

Answer 12

• Make a product on a large scale
• Make only one product
• Operate all the time
• can run automatically

Question 13

Name three facts about Batch Process?

Answer 13

• makes a product on demand and on small scale
• can be used to make a variety of products
• Labour Intensive

Question 14

What happens in a Batch process

Answer 14

• Reactants are put into a reactor and the product is removed at the end of the reaction

Question 15

In a chemical reaction, which process is involved with breaking bonds?

Answer 15

• Endothermic

Question 16

How can Atom Economy be calculated?

Answer 16

Atom economy =

mr of desired product x100
➖➖➖➖➖➖➖➖➖➖➖➖➖➖➖➖➖
Sum of Mr of All the products

Question 17

What is atom economy ?

Answer 17

• A way of measuring the number of atoms that are wasted in a chemical reaction

Question 18

In a chemical reaction, which process in involved with making bonds?

Answer 18

• Exothermic

Question 19

How do you work out the energy transferred per gram of fuel burned

Answer 19

Energy per gram =

Energy supplied
➖➖➖➖➖➖➖➖➖➖➖➖
Mass of fuel burned

Question 20

How do you work out the energy transferred ?

Answer 20

Energy transferred=

Mass of water heated ✖️ SHC ✖️ change in temp

Question 21

How do you find the change in temperature?

Answer 21

Final temp ➖ start temp

Question 22

What can a calorimeter be used for?

Answer 22

• Can be used to compare the amounts of heat energy released by the combustion of different fuels

Question 23

What happens from an Endothermic reaction?

Answer 23

• Endothermic reactions absorb energy from the surroundings and cause a temperature drop

Question 24

What happens from an Exothermic reaction?

Answer 24

- Exothermic reactions release energy to the surroundings and cause a temperature rise

Question 25

Why could percentage yield be lower than the expected yield?

Answer 25

- product could be lost in evaporation, filtration or during the transfer of liquids

Question 26

How do you work out percentage yield?

Answer 26

Percentage yield= Actual yield ➖➖➖➖➖➖➖➖➖➖ ✖️100 Predicted yield

Question 27

What happens to the number of atos during a reaction?

Answer 27

- It stays the same, they are just rearranged into different substances

Question 28

The mass of the product produced = ......

Answer 28

The mass of the starting materials

Question 29

How do you calculate relative formula mass?

Answer 29

1- write down the formula of the compound 2- multiply the number of atoms of each element in the formula by its atomic mass 3- add all up

Question 30

How do you find the relative atomic mass of an element?

Answer 30

- The top/larger number of an element

Question 31

Describe the particles in a reaction with a high concentration?

Answer 31

- the particles will be close together they will collide more often

Question 32

Describe particles in a reaction where the gas is under high pressure?

Answer 32

- they are crowded together

Question 33

Describe the particles in a reaction where the gas is under low pressure?

Answer 33

- They are spread

Question 34

How does the surface area of a reactant affect the speed of the reaction?

Answer 34

- The larger the surface area, the faster the reaction

Question 35

What is relative formula mass?

Answer 35

- the sum of all the atoms present in the formula

Question 36

What do more energetic collisions lead to?

Answer 36

- more successful collisions

Question 37

Describe the particles in a reaction with a low consentration?

Answer 37

- The particles will be spread out. Therefore the particles will collide less often

Question 38

What do more frequent collisions between particles lead to?

Answer 38

- a faster reaction

Question 39

When do chemical reactions happen?

Answer 39

- when particles collide with enough energy

Question 40

What does the amount of product formed depend on?

Answer 40

- the amount of reactant used

Question 41

What does increasing temperature cause in a reaction?

Answer 41

- an increase in kinetic energy, of the particles

Question 42

When do chemical reactions stop?

Answer 42

- When one of the reactants is used up

Question 43

How can the rate of reaction be increased?

Answer 43

- raising the temperature - increasing concentration (liquids) - increasing pressure (gases)

Question 44

What speed do particles move in a reaction with a high temperature?

Answer 44

- fast

Question 45

What speed do partials move in a reaction with a low temperature?

Answer 45

- slowly