chemisty
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| 🇬🇧 | 🇬🇧 |
| Alkane symbol | Here |
| Ethane symbol | Here |
| Ethanol, alcohol | Here |
| Monkeys, eat, peanut, butter | Methane (4 h's), ethane (6 h's), propane (8 h's), butane (10 h's) |
| What things produce carbon dioxide during combustion | Coal, natrual gas and petroleum (these are fossil fuels) |
| What is petroleum made up of | Mixture of hydrocarbons |
| How is petroleum seperated | Using fractional distillation which can create usefull fractions |
| Cracking of petroleum products, bottom to top | Bitumen (for road sufraces), fuel oil (fuel for ships and power stations), diesel (fuel for cars, lorries and buses), kerosene (aircraft fuel), gasoline (fuel for cars), refinary gas (bottled gas) |
| What are the properties of the molecules at the top of the cracking of petroleum | Low boiling point, very volatile, flows easily, ignites easily |
| What are the properties of the molecules at the bottom of the cracking of petroleum | High boiling point, not very volatile, does not flow easily, does not ignite easily |
| Compounds in homogolous series have.... part 1 | Same chemical reactions, same functional group (c=c for alkenes, -OH for alcohols) |
| Compounds in homogolous series have.... part 2 | Same general formula, similar phyiscal properties |
| What are alkanes | Saturated hyrdrocarbons (single covalent bonds) |
| Properites of alkanes | Typically unreactive, except when burning |
| What is the general formula for alkanes | CₙH₂ₙ₊₂ is the general formula for alkanes |
| What does the complete combustion of hyrocarbons give off | Carbon dioxide and water |
| What are alkenes | Un saturateed hydrocarbons (contain one double covalent bond, double bonds between the carbons) |
| What is cracking | Reaction (alkanes to alkenes) |
| Needed factors for cracking | 550 degress c |
| Needed factors for craking | Catalyst of aluminium oxide and silicon oxide |
| What does cracking large alkanes produces | A smaller alkane and alkene and hydrogen |
| Test for saturated hydrocarbons | Identified by their reaction with aqueous bromine (bromine water). If saturated, then it will turn from orange/brown to colourless |
| Are alkenes more reactive? | Yes because they are unsaturated so they form polymers |
| What is hydrogenation | With a catalyst, alkenes can react with hydrogen and heat to make alkanes |
| What is hydration | With a catalyst, alkenes can react with steam(water) and around 300°C to make alcohols. |
| How can ethanol or alcohol be produced | By fermentation and/or by reaction between ethene and steam |
| Describe fermentation | This requires glucose, temperatures of around 30°C, anaerobic conditions and uses the enzymes in yeast. Glucose → ethanol + carbon dioxide |
| What does the complete combustion of alcohols produce | Carbon dioxide |
| What are polymers | Long chain of monomers formed from smaller units (Monomers) |
| What temp does calcium carbonate (limestone) thermally decompose at, and the symbol equation | 840°C to become calcium oxide (lime). CaCO3(s) + heat → CaO(s) + CO2(g) |
| What type of reaction is this | Reversible, so the carbon dioxide needs to be removed otherwise it will react with the calcium oxide to make calcium carbonate again. |
| What is lime used for | Manage the acidity of soil and industrial waste to neutralise it. For example sulphur dioxide produced by factories can be neutralised with lime so that it doesn’t cause acid rain. |
| What is added to sulphur trioxide to make sulphuric acid | Water, this reaction is not reversible |
| What is sulfur used to manufactor in the contact process | Sulphuric acid, for this reaction : sulphur, air and water in needed |
| What is added to sulphur trioxide to make sulphuric acid | Water, this reaction is not reversible |
| What is added to sulphur trioxide to make sulphuric acid | Water, this reaction is not reversible |
| What do we do with the sulphur first | Burned to the air |
| What happens when the sulphur burned in the air | Reacts with oxygen to make sulphur dioxide. Sulphur dioxide is highly dangerous as it contributes to acid rain |
| Symbol equation of reaction of sulphur and oxygen | This reaction is not reversible. S + O2 → SO2 |
| Factors of the contact process | 450 degrees |
| Factors of the contact prcoess | 2 atmospheres |
| Factors of the contact process | Vanadium catalyst |
| After sulphur + oxygen reaction, what is the next reaction | Sulphur dioxide reacts with oxygen to make sulphur trioxide. This reaction is reversible. 2SO2 + O2 ⇌ 2SO3 |
| What is added to sulphur trioxide to make sulphuric acid | Water, this reaction is not reversible |
| Why is the addition of water to sulphur trioxide bad | Highly dangerous and exothermic as it forms clouds of hazardous sulphuric acid |
| How do we fix the dangers of adding water to sulphur trioxide | Sulphur trioxide is added to concentrated sulphuric acid to make oleum (H₂S₂O₇), which is then reacted with water to make sulphuric acid again. SO3 + H2SO₄ → H₂S₂O₇ then H₂S₂O₇ + H2O → 2H2SO₄ |
| Testing for water | Copper (II) sulphate: Anhydrous or ‘dehydrated’ (and pure) copper (II) sulphate is white. When water is present in anhydrous copper(II) sulphate it turns blue, becoming hydrous copper (II) sulphate |
| Testing for water | Cobalt (II) chloride: Anhydrous or ‘dehydrated’ (and pure) cobalt (II) chloride is blue. When water is present in anhydrous cobalt (II) chloride it turns pink, becoming hydrous cobalt (II) chloride. |
| Purifying water | Filtration: The different sized insoluble particles are filtered out of the water using filters |
| Purifying water | Chlorination: Chlorine is injected into the water and it sterilises it, killing the microbes |
| Percentages of the things in clean air | 78% nitrogen, 21% oxygen and small quantities of noble gases, water vapour and carbon dioxide. |
| What are the common pollutants in air | Carbon monoxide, sulphur dioxide and nitrogen oxides |
| Where does carbon monoxide come from | Incomplete combustion of carbon-containing substances, |
| Why is carbon monoxide bad | Carbon monoxide poising : causes breathing problems as it reduces the amount of red blood cells in the body |
| Where does sulphur dioxide come from | Combustion of fossil fuels which contain sulphur compounds |
| What does sulphur dioxide lead to | Lead to acid rain which corrodes metal, erodes stone work and can kill plants and aquatic life. |
| Whre does nitrogen oxides come from | Car engines |
| What does nitrogen oxide potentially lead to | React with other pollutants to form smog which causes difficulty in breathing. It also causes acid rain. |
| What can a catalyic converter do (for the bad stuff) | Used to remove nitrogen monoxide and carbon monoxide from exhaust emissions through the reaction over a hot catalyst. |
| What can be carbon monoxide be oxidied to | Become carbon dioxide. 2CO + O2 → 2CO2 |
| What can nitrogen monoxide be reduced to | Nitrogen and oxygen. 2NO → N2 + O2 |
| Conditions for rusting of iron. | The presence of oxygen and water vapour in air |
| How can rusting be stopped | By encasing the metal with paint, oil, grease or coating with plastic |
| How can rusting be stopped | Sacrificial protection, implementing the reactivity scale |
| Examples of sacrificial protection | Iron can be coated (galvanised) with zinc as zinc is more reactive than iron, and it oxidises more readily than the iron. After the sacrificial metal has been corroded then it can be replaced. |
| How can be carbon dioxide get formed | As a product of complete combustion of carbon-containing substances |
| How can be carbon dioxide get formed | As a product of respiration |
| How can be carbon dioxide get formed | As a product of the reaction between an acid and a carbonate |
| How can be carbon dioxide get formed | As a product of thermal decomposition of calcium carbonate |
| What type of gas is carbon dioxide and methane | Greenhouse gases |
| What is nitrogen, phosphurus and potassium needed for | Fertilisers as they provide the mineral ions required for healthy growth in plants |
| Fertlisers must be | Soluble in water so that the root hair cells in the plants can absorb the ions. |
| How do we create ammonia | Habor process, reversible reaction |
| Factors of ammonia | 450 degrees |
| Factors of ammonia | 200 atmopheres |
| Factors of ammonia | Iron catalyst |
| What is metallic bonding made up of | Lattice of positive ions in a ‘sea of electrons’ |
| What are alloys | Alloys, such as brass and steel, are mixtures of a metal with other elements |
| Are alloys stronger than pure metals or not? | Alloys are stronger |
| Reactivity series | Potassium, sodium, calcium, magnesium, aluminium, (carbon), zinc, iron, (hydrogen) and copper is the reactivity series from most reactive to least reactive. |
| What happens if a metal is less reactive than carbon | It can be extracted from its oxide by heating with carbon, and the metal is displaced. |
| Exmaples of extraction with carbon (as coke) | Iron, for example, is extracted from iron ore in the blast furnace. Iron ores, such as haematite contain iron oxide, which can be reduced using carbon to obtain the iron. This reaction looks like this: 2Fe₂O₃(s) + 3C(s) → 4Fe(l) + 3CO₂(g) , Iron oxide + Carbon → Iron + Carbon dioxide |
| Exmaples of extraction with carbon (as coke) | Calcium carbonate (limestone) is added into the blast furnace to remove the impurities from the haematite such as silica (sand). |
| Examples of extraction with carbon (as coke) | The CaCO₃ (limestone) thermally decomposes to become calcium oxide which reacts with silica (SiO₂) to form calcium silicate (CaSiO₃), also known as slag which is then funnelled out so, in the blast furnace only pure iron is left. |
| How is aluminium extracted | From bauxite, through electrolysis. |
| When does electrolysis work | Extract any metals that are more reactive than carbon, such as aluminium, magnesium and calcium. |
| Uses of metals | In aircraft parts because of its strength and low density, in food containers because of its resistance to corrosion. |
| Uses of metals | Car bodies and machinery |
| Uses of metals | Chemical plants and cutlery |
| Uses of metals | Used to galvanise (coat/plate) iron or steel to protect them from rusting. For example galvanised steel can be used on roofs as it is weather resistant. |
| What are noble gases | Are unreactive, monoatomic gases because of their full outer shells. |
| What are noble gases | Are unreactive, monoatomic gases because of their full outer shells. |
| What do all noble gases do | They are all used to provide inert atmospheres as they are inert (non reactive) |
| What happens as we go down in group 1 | The reactivity increases |
| What happens as we go down in group 7 | The reactivity decreases |
| What are alkali metals | Lithium, sodium and potassium (Group I) are a collection of relatively soft metals with an increasing trend in melting point, density and reactivity with water. |