Chemistry finals

Question 1

What is polymers made of

Answer 1

monomers

Question 2

How do you test for alkenes

Answer 2

bromine water will change from brown to colourless

Question 3

side effects of carbon monoxide

Answer 3

Carbon monoxide attaches to haemoglobin and reduces the ability to carry oxygen

Question 4

Name the 6 different crude oil fractions and uses

Answer 4

Petroleum gas: domestic heating
Petrol: car
kerosene: planes
diesel: trucks
heavy fuel oil: ships
bitumen: road surfacing

Question 5

wat 3 factors will change as the numbers of carbons will increase

Answer 5

Visosity increase
Colour darker
Melting and boiling increases

Question 6

name the first 6 alkanes

Answer 6

methane
ethane
propane
butane
pentane
hexane

Question 7

definition of hydrocarbons

Answer 7

a compound that only contains only hydrogen and carbon

Question 8

name 2 reversible reactions

Answer 8

thermal decomposition of ammonium chloride
copper sulfate

Question 9

How do catalyst speed up reaction

Answer 9

A catalyst provides an alternative reaction pathway that has a lower activation energy than the uncatalysed reaction

Question 10

What are the 4 factors that affect rate of reaction

Answer 10

Concentration
Temp
SA
Catalyst

Question 11

Formula to calculate heat energy change

Answer 11

Q = M x C x T

Question 12

What is endothermic reaction

Answer 12

chemical reactions in which the reactants absorb heat energy from the surroundings to form products.

Question 13

What is exothermic reaction

Answer 13

When energy is transferred to the surroundings

Question 14

Test and result for
Water

Answer 14

anhydrous copper sulfate will turn from white to blue if water is present

Question 15

what is test for chloride, bromide and iodide

Answer 15

add dilute nitric acid

Question 16

positive result for chloride

Answer 16

white

Question 17

positive result for bromide

Answer 17

cream

Question 18

positive result for iodide

Answer 18

yellow

Question 19

test and result for iron(iii)

Answer 19

Sodium Hydroxide
Red-brown

Question 20

test and result for iron

Answer 20

Sodium hydroxide
Green preciptate

Question 21

Test and result for copper

Answer 21

Sodium hydroxide
Blue preciptate

Question 22

colour of flame when copper added

Answer 22

green

Question 23

colour of flame when calcium

Answer 23

orange-red

Question 24

colour of flame when potassium

Answer 24

lilac

Question 25

colour of flame when sodium

Answer 25

yellow

Question 26

colour of flame when lithium

Answer 26

red

Question 27

test and result for chlorine

Answer 27

blue litmus paper is bleached

Question 28

test and result for ammonia

Answer 28

red litmus turns blue

Question 29

Colour of phenol-phthalien paper in acid, alkali and neutral

Answer 29

acid: colourless alkali: pink Neutral: colour-less

Question 30

3 ways to prevent rusting

Answer 30

Barrier method - painting, grease, oil Galvanising - apply layer of zinc, zinc more reactive so it will oxidise first Sacrificial method - cover with more reactive metal

Question 31

What is thermal decomposition

Answer 31

Thermal decomposition is the term used to describe reactions where a substance breaks down due to the action of heat

Question 32

what colour is iodine and what is the state at room temp

Answer 32

black and solid

Question 33

what colour is bromine and what is the state at room temp

Answer 33

brown and liquid

Question 34

what colour is chlorine and what is the state at room temp

Answer 34

yellow and gas

Question 35

what colour is fluorine and what is the state at room temp

Answer 35

Yellow and gas

Question 36

Which halogen is liquid room temp

Answer 36

Bromine

Question 37

What does Metal + water form

Answer 37

Metal hydroxide + hydrogen

Question 38

what does Metal + acid form

Answer 38

salt + hydrogen

Question 39

What does metal + oxygen form

Answer 39

metal oxide

Question 40

State the 3 properties of diamond

Answer 40

It doesnt conduct electricity high melting and boiling point High density

Question 41

Explain why graphite can conduct electricity

Answer 41

electrons migrate along the layers and are free to move and carry charge, hence graphite can conduct electricity

Question 42

What is an ionic bond

Answer 42

The positive and negative charges are held together by the strong electrostatic forces of attraction between a non-metals and a metal

Question 43

What is a covalent bond

Answer 43

A covalent bond consists of the mutual sharing of one or more pairs of electrons between 2 non-metals

Question 44

What is a negative ion called

Answer 44

anions

Question 45

What is a positive ion called

Answer 45

cation

Question 46

What is a mole

Answer 46

A ‘mole’ simply refers to the amount of a certain substance

Question 47

What is a isotope

Answer 47

Isotopes are atoms which have the same number of protons but different numbers of neutrons.

Question 48

formula for molar mass

Answer 48

Mr = m/n n= amount of moles m= mass mr= molar mass

Question 49

Describe what will happen to the particles in a room with a radiator refer to convection

Answer 49

The particles next to the radiator will gain heat energy causing these particles to move faster and move apart from one another. This makes the hot air expand and become less dense, causing it to rise and displace colder air. The colder air will fall to spot next to the radiator and itself heat up and rise. This creates cycles of fluid movement which we call convection currents