Chemistry As Level Ocr B

Front 1

Percentage yield equals

Back 1

Experimental yield/theoretical yield *100

Front 2

Properties of ionic structures.

Back 2

Often soluble

Conduct when molten or dissolved in water.

High melting and boiling points.

Front 3

Properties of giant covalent structures.

Back 3

Insoluble.

Do not conduct. (Graphite is an exception.)

Very high boiling points.

Front 4

Properties of simple molecular structure.

Back 4

Insoluble.

Do not conduct.

Low boiling points.

Front 5

Properties of metallic structures.

Back 5

Usually insoluble.

Conduct in solid and liquid form.

High melting and boiling points.

Front 6

How many electrons are there in the s,p,d and f orbitals.

Back 6

S orbital holds 2 electrons

P orbital hold 6 electrons

D orbitals hold 10 electrons.

F orbitals hold 14 electrons.

Front 7

What fills first 4s or 3d.

Back 7

4s fills first however there is an exception to the rule in copper and chromium where the 4s is left with one.

Front 8

Bond angles.

Back 8

Linear=180°

Planar=120°

Tetrahedral (no lone pair of electron.s)=109.5°

Tetrahedral (one lone pair of electrons.)=107.0°

Tetrahedral (two lone pairs of electrons.)=104.5°

Bipyramidal=90° and 120°

Front 9

Table of tests for cations and anions.

Back 9

Cations are positive.

Anions are negative.

Front 10

Concentration equation.

Back 10

Amount (in moles)/volume(dm3)

Front 11

100 Celsius to Kelvin.

Back 11

100+273= 373 kelvin

Front 12

Working out energy transferred using specific heat capacity.

Back 12

Energy transferred= specific heat capacity×mass (g)×temperature change(k)

Front 13

What's the difference between a benzene ring and cyclohexane?

Back 13

Half of the bonds in a benzene ring are double bonds, cyclohexane has no double bonds.

Front 14

What is the difference between an aromatic and aliphatic molecule?

Back 14

Aromatic compounds contain one or more benzene ring, aliphatic compounds do not contain any benzene rings.

Front 15

What are the steps for cracking?

Back 15

1: Reactants are adsorped onto the catalyst surface.

2: Bonds in the reactants break.

3:New bonds are formed.

4: Product diffuses from the catalyst surface.

Front 16

What are the steps of electrophilic addition with bromine?

Back 16

1: Bromine is a polar molecule, electron from carbon double bond goes to slightly positive bromine atom. Electron in bromine bond goes to the other bromine atom.

2: Bromine atom bonds to carbon, this leaves a carbon with a positive charge and a bromine with a negative charge.

3: The other bromine bonds to the positive carbon.

Front 17

How do you make ethanol from ethene?

Back 17

Under high pressure and temperature, firstly add concentrated sulphuric acid, then add water.

Front 18

What is a carbonation?

Back 18

A carbon ion with a positive charge.

Front 19

What is a single and double bonds chemical name?

Back 19

Single bond = sigma.

Double bond = pi

Front 20

How does addition polymerization occur?

Back 20

Occurs between hydrocarbons with carbon double bonds. These doubles bonds open up and form single bonds between monomers. In addition polymerization the only product is the polymer.

Front 21

Ideal gas equation. PV=nRT

Back 21

P=pressure in Pascal's.

V=volume in m3.

n=number of moles.

R=gas constant.

T=temperature in Kelvin.

Front 22

What is E/Z isomerism?

Back 22

Isomerism is where two molecules have the same structural formula but their atoms are arranged differently. E is trans z is cis. Trans is where the chain/special atoms are on either side of the double bond.

Front 23

What is the equation for complete combustion?

Back 23

Hydrocarbon+oxygen➡️carbon dioxide+water.

Front 24

Equation for the production of acid rain.

Back 24

SO2+H2O➡️H2SO3

Front 25

Formation of nitric acid for acid rain.

Back 25

2NO+H2O+1.5O2➡️2HNO3

OR

2NO2+H2O+0.5O2➡️2HNO3

Front 26

What is photochemical smog?

Back 26

Pollutant caused by ozone and nitrogen dioxide. Causes haziness and reduced visibility in the air as well as respiratory problems.

Front 27

What is a catalytic converter?

Back 27

A device that converts pollutants in car exhaust's into less harmful substances. They work at 150° and consist of platinum and rhodium. They are poisoned by lead so they only work with lead free fuels.

Front 28

What are the equations for removing pollutants in a car engine?

Back 28

2CO+O2➡️2CO2

C7H17+11O2➡️7CO2+8H2O

2NO+2CO➡️N2+2CO2

Sulfur is removed from the fuels before it is available.

Front 29

How is nitrogen oxide removed from diesel engines?

Back 29

It is reacted with ammonia and oxygen to form nitrogen and water.

4NO+4NH3+O2➡️4N2+6H2O.

Front 30

What is the colour of halogens dissolved in water?

Back 30

Iodine- pale green

Chlorine- orange

Iodine-brown

Front 31

What is the colours of the halogens dissolved in cyclohexane?

Back 31

Chlorine- pale green

Bromine- orange

Iodine- violet.

Front 32

What is the test for halide ions?

Back 32

Add silver nitrate.

Silver chloride white

Silver bromide cream

Silver iodide yellow.

Dissolve in ammonia

Silver chloride dissolves easily.

Silver bromide dissolves slowly.

Silver iodide does not dissolve.

Front 33

What are the exceptions to the rule of electrolysis in solutions?

Back 33

Hydrogen or metal at cathode.

Oxygen, halogen or other non metallic atom at unreactive anode.

Copper ions at copper anode.

Front 34

What is the equation for Kc?

Back 34

If aA+bB🔁cC+dD.

Then Kc = (C)^c * (D)^d/(A)^a *(B)^b

Front 35

What is the formula for percentage atom economy?

Back 35

% atom economy= relative formula mass of the desired /relative formula mass of all the reactants. *100

Front 36

Reactions of halides with different substances?

Back 36

In solution halides are acidic.

Hydrogen halides react with ammonia to form salts. NH3+HCl➡️NH4Cl.

Front 37

How do hydrogen halides react with sulfuric acid?

Back 37

Hydrogen fluoride and chloride don't react.

Hydrogen bromide forms SO2.

Hydrogen iodide forms H2S.

Front 38

What is the deacon process?

Back 38

A process of producing chlorine while remove hydrogen chloride gas.

Front 39

What is le chatelier's principle?

Back 39

An equilibrium will directly oppose any change made to it.

Front 40

What affects the position of equilibrium?

Back 40

Changing pressure.

Changing temperature.

Changing the concentration of a product or reactant.

Increasing temperature will shift the equilibrium to the endothermic reaction.

Increasing pressure will shift it to the side with the least number of moles.

Increasing products will shift it towards the reactants.

Front 41

What are the four types of electron behaviour?

Back 41

Translation- caused by radiation of frequency less than microwaves.

Rotation- caused by microwave radiation.

Vibrational-caused by infra red radiation.

Excitation/ionisation- visible light or ultraviolet radiation.

Front 42

What is the difference between dissociation and ionisation?

Back 42

Ionisation is where the electrons are excited so much that they leave an atom, this forms ions.

Dissociation is where the electrons are excited to a point where they break the bond between two atoms, this forms radicals.

Front 43

What are radicals?

Back 43

Molecules or atoms with at least one pair of unpaired electrons.

Front 44

What is the difference between heterolytic and homolytic fission?

Back 44

Heterolytic fission is where both electrons in a bond goes to one of the atoms. It is common in polar bonds, it forms ions.

Homolytic fission is where both atoms receive the same number of electrons, this forms radicals.

Front 45

What represents the movement of electrons?

Back 45

A curly arrow.

Front 46

What are the three stages of chlorine breaking down the ozone layer?

Back 46

Initiation- Cl2➡️Cl⚫+Cl⚫

Propagation- Cl⚫+O2➡️ClO⚫+O⚫

Termination-Cl⚫+Cl⚫➡️Cl2

Front 47

What causes permanent dipoles to be made?

Back 47

One atom in a bond is much more electronegative than the other this means the electrons are situated closer to them. This makes them slightly negative.

Front 48

What causes an induced dipole?

Back 48

An induced dipole is created if an unpolarized molecule is next to a dipole. The dipole attracts/repels the electrons in the unpolarized molecule causing an induced dipole.

Front 49

How is hydrogen bonding represented?

Back 49

With lots of lines.

Front 50

What elements can form hydrogen bonds?

Back 50

Fluorine, oxygen and nitrogen.

Chlorine cannot as it is too big.

Front 51

What is a nucleophile?

Back 51

A nucleophile is a molecule or negatively charged ion with a lone pair of electrons that it can donate to a positive ion.

Front 52

What happens when primary alcohols are oxidised?

Back 52

They become aldehydes with no reflux.

They become carboxylic acid with oxidising agent in excess and under reflux.

Front 53

What happens to primary, secondary and tertiary alcohols when they are oxidised with potassium dichromate solution?

Back 53

Primary alcohol- aldehyde or carboxylic acid. Turns green.

Secondary alcohol- Ketone. Turns green.

Tertiary alcohol- does not oxidised. Remains orange.

Front 54

What conditions are required for the dehydration of alcohols?

Back 54

300° catalyst under reflux with concentrated sulfuric acid.

Front 55

What are the two types of esterification?

Back 55

1:Alcohol+carboxylic acid=ester+water. Under reflux with strong acid present.

2:Alcohol+acid anhydride=ester+carboxylic acid.

Front 56

What happens to iron(3) chloride if a phenol is present?

Back 56

It goes purple.

Front 57

What are the steps of recrystallization?

Back 57

1:Select a solvent in which the desired product is very soluble at high temperatures but insoluble at low temperatures.

2:Dissolve the mixture into the heated solvent and filter it, this will remove any insoluble impurities.

3:leave the filtrate to form crystals, collect these crystals using vacuum filtration.

4:wash the crystals with cold solvent and dry them.

Front 58

List of functional groups.

Back 58

Alcohol R-OH name ends in ol.

Ether R-O-R name is oxy ane.

Aldehyde. R-C-H name is al.

⏸️

O

Carboxylic acid has -ooh name is oic acid.

Ester-OOR. Name is yl oate.

Arene- benzene ring with hydrocarbon chain.