C1 last minute exam revision tips! TOPIC 1: The Earth and its Atmosphere EARLY ATMOSPHERE: Volcanic eruptions Huge amounts of CARBON DIOXIDE and WATER VAPOUR being released. Small amounts of methane and ammonia were also released. Over time the Earth began to COOL down. The water vapour condensed to form the oceans. Some of the carbon dioxide DISSOLVED in the oceans. Primitive plants evolved and took in more carbon dioxide, through the process of PHOTOSYNTHESIS. OXYGEN was released as a waste product.

C1 last minute exam revision tips! Topic 2: Rocks and their formation 3 types of rocks: Sedimentary Igneous Metamorphic Igneous rocks form when molten rock cools down. When magma cools SLOWLY beneath the Earth’s surface, it forms intrusive igneous rock. These have LARGER crystals. When lava is released from a volcanic eruption it cools QUICKLY, forming EXTRUSIVE igneous rocks. These have SMALLER crystals. Sedimentary rocks form when bits of broken down rocks settle at the bottom of rivers or lakes. They form LAYERS OF SEDIMENTS. This process takes millions of years. Fossils may be contained in sedimentary rocks. Metamorphic rocks form when rocks are subjected to HIGH pressures and HIGH temperatures.

C1 last minute exam revision tips! Topic 2: Rocks and their formation Calcium carbonate (limestone) cycle: Thermal decomposition is the breakdown of CaCO3 using heat. Calcium hydroxide is the chemical name for LIMEWATER.

C1 last minute exam revision tips! Topic 3: ACIDS & ELECTROLYSIS Hydrochloric acid is present in the stomach to help digest food and kill bacteria. H2SO4 HNO3 HCl

Hydrochloric acid HCl Sulfuric acid H2SO4 Nitric acid HNO3 CHLORIDE SALT HCl E.G. Magnesium oxide + hydrochloric acid  Magnesium chloride + water Sulfuric acid SULFATE SALT H2SO4 E.G. Magnesium hydroxide + sulfuric acid  Magnesium sulfate + water Nitric acid NITRATE SALT HNO3 E.G. Calcium carbonate + nitric acid  calcium + water + carbon dioxide nitrate

C1 last minute exam revision tips! Topic 3: ACIDS & ELECTROLYSIS Electrolysis is a process which uses electricity to split-up compounds.

C1 last minute exam revision tips! Topic 3: ACIDS & ELECTROLYSIS Gas tests: Hydrogen gas, H2- place a lit splint into the test-tube SQUEAKY POP. Oxygen gas, O2 – RELIGHTS a GLOWING splint. Chlorine gas, Cl2 – Damp blue litmus paper, bleached white.

C1 last minute exam revision tips! Two methods of extraction: Topic 4: Metals and ores ABOVE CARBON; MORE REACTIVE; EXTRACTED BY ELECTROLYSIS. Two methods of extraction: Heating with carbon Electrolysis An ore is a naturally occurring rock that contains metals or metal compounds, which can be extracted for profit. BELOW CARBON; LESS REACTIVE; EXTRACTED BY HEATING WITH CARBON. UNREACTIVE!

Reduction and oxidation Carbon + copper oxide  copper + carbon dioxide Key - we are removing oxygen from the copper. This is what happens in metal extraction. This is called REDUCTION. ** Reduction is the removal of oxygen. Copper + oxygen  copper oxide This is called OXIDATION ** Oxidation is the addition of oxygen.

C1 last minute exam revision tips! Topic 4: Metals and ores Recycling metals: The Earth’s resources are LIMITED and it is important that we CONSERVE as much as possible. One way to do this is to RECYCLE waste products.

Topic 4: Metals and ores: RECYCLING METALS Advantages Disadvantages Helps to limit the amount of metals that must be produced. Limits the use of landfill sites. Adds jobs to the economy. Slows the consuming of natural resources (CONSERVES natural ores). Process of recycling metals usually creates (much) less pollutants and greenhouse gases than extracting that metal from its ore. Uses less energy therefore less fossil fuels are being burnt. The collection and sorting of domestic materials to be recycled can be expensive, time consuming and require energy.

CRUDE OIL is a mixture of hydrocarbons. Topic 5: CRUDE OIL is a mixture of hydrocarbons. A mixture of hydrocarbons are separated according to boiling points. Hydrocarbons are substances that are made up of CARBON and HYDROGEN ONLY. The process is called FRACTIONAL DISTILLATION.

Alkanes & Alkenes What is the general formula for saturated alkanes? General Formula for alkanes is CnH2n+2 How about for unsaturated hydrocarbons? General Formula for alkanes is CnH2n TEST FOR ALKENES USING ORANGE BROMINE WATER!!!

A HYDROCARBON is A compound made of ONLY HYDROGEN AND CARBON. C is NOT a hydrocarbon because it has an OXYGEN and CHLORINE atom in its compound! Mohammed Anwar Hussain © 2016

Fractional distillation Remember the NAME of the process! Short Chains Lower boiling points This process separates the hydrocarbons according to their boiling points! Remember the NAME of the process! Longer Chains Higher boiling points

Cracking A process where long hydrocarbons are broken down into SMALLER MORE USEFUL hydrocarbons and alkenes. Cracking reduces the demand for fractions with smaller hydrocarbons. Conserves natural crude oil reserves as well.

Octane + OXYGEN  carbon dioxide + water Combustion 2 types of combustion COMPLETE & INCOMPLETE Combustion is a process of burning. When a fuel burns in air it forms CARBON DIOXIDE AND WATER. E.g. Octane + OXYGEN  carbon dioxide + water

Toxic chemical (POISONOUS GAS) Incomplete combustion Carbon monoxide Toxic chemical (POISONOUS GAS) Dirty Your red blood cells BIND to carbon monoxide rather than oxygen. As a result your blood has less or very little oxygen. Vital ORGANS receive insufficient amounts of oxygen. You start to feel DIZZY, SICK, FAINT… DEATH Causes breathing problems Causes black smoke = soot to be formed. This is pure carbon. It also forms carbon monoxide. CO2 CO How are they different?

THIS HAS NOTHING TO DO WITH THE OZONE LAYER SO DO NOT MENTION IT!!!!!! ACID RAIN COAL contains SULFUR impurities. When coal burns SULFUR DIOXIDE is formed Sulfur dioxide is an ACIDIC GAS. This causes ACID RAIN. GREENHOUSE GASES CARBON DIOXIDE CO2 Absorbs HEAT energy (ALSO CALLED INFRARED RADIATION) Increases Earth’s Temperature THIS HAS NOTHING TO DO WITH THE OZONE LAYER SO DO NOT MENTION IT!!!!!!

Alternative fuels- BIOFUELS Advantages Disadvantages They are a renewable resource. Energy is needed to manufacture the fertiliser for the crops and to harvest them. The energy is supplied from fossil fuels. They are easily sustainable. Energy is needed to process them into biofuel. The energy is supplied from fossil fuels. May help reduce the overall amount of carbon dioxide that human activity puts into the atmosphere. Fuel is needed to transport the biofuels (importation from other countries or fuel for large lorries and trucks). The energy is supplied from fossil fuels. Biofuels can be carbon neutral (overall, it does not add carbon dioxide to the atmosphere). A lot of crop would need to be grown to make the biofuel, which means less farmland for growing food. Reduce the demand on fossil fuels and conserve crude oil supplies. A lot of land will be needed to plant biofuel crops (may lead to deforestation).

What makes a good fuel? KEY THINGS TO REMEMBER! Q: Evaluate the advantages and disadvantages of using hydrogen as an alternative fuel, compared with fossil fuels such as petrol (6). What makes a good fuel? When hydrogen and oxygen combust the only product is water ‘a clean fuel’; No harmful gases are released into the environment. Hydrogen is very efficient – producing A LOT of energy PER UNIT MASS; NOTE: HYDROGEN IS PRODUCED FROM NATURAL GAS WHICH PRODUCES CO2 Before it can be used wide scale it has to be easily available & easily transported; However the gas has to be stored at high pressure; Filling stations would have to be converted; Cars would also have to produced. KEY THINGS TO REMEMBER! How easily it burns. How much energy it produces. How easy it is to transport and store.

The double bond is very reactive! Polymerisation The double bond is very reactive! Each of these ethene molecules are called monomers. When they react together, the double bond ‘opens’; they form a polymer. This polymer, which is made up of ethene monomers is called poly(ethene).

Repeating units (higher tier)

OPTIONS PROBLEMS WITH POLYMERS Although polymers derived from alkenes are invaluable to modern society, their disposal creates widespread problems. • they are unreactive to most chemicals • they are unreactive to bacteria (non-biodegradable) • if they are just discarded they add to the landfill problem OPTIONS recycling high cost of collection and re-processing incinerate saves on landfill sites and produces energy which can be used to generate electricity but… produces toxic fumes Plastic bags are being made from polymers and cornstarch so that they break down more easily