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Explain, giving examples from the articles EssayExplain, giving examples from the articles, what is meant by oxidation and collection how oxidation reactions ar calld to creator explosions. Outline reasons why some fickle mixtures oxidise speedy than others. 4 An element is oxidised if It gains oxygen. It loses electrons. Its oxidation state change magnitudes. Explosives much(prenominal) as gun gunpowder or black powder contain powdered carbon, sulphur and atomic number 19 nitrate. This can be ignited by a fusee where carbon and sulphur leave alone be oxidised. Carbon will form into Carbon Dioxide and Sulphur will form into Sulphur Dioxide. This reaction shows when a pure sample of carbon burns in air. C(s) + O2(g) i CO2(g) This is an oxidation reaction where carbon has gained oxygen and its oxidation state has increased from 0 to +4 The potassium nitrate in the gunpowder acts as an oxidiser and provides oxygen for the reaction. All the oxygen required is accessible almost instantly therefore carbon and sulphur burn in a fraction of a second. The reactants and harvest-times of this reaction atomic number 18 Reactants KNO3(s) C(s) S(s) Products CO2(g) SO2(g) N2(g) + Other solid products The intensiveness of the reactants is very sm on the whole.The products are mainly hot gases produced absolutely in a confined area. This rapid increase in squash leads to an explosion. (132 Words) To maximise the force of the reaction, all solids involved are finely divided into powders and the proportions of reactants in the mixture are calculated very accurately. The federal agency of the explosion is made greater by confining the reaction inside a restricted aloofness e. g. Cannon. Fuels used in fireworks Potassium Chloride (KClO3) and rockets Hydrogen Peroxide (H2O2) are mixed with oxidisers to produce explosions.Some volatile mixtures oxidise faster than others if the reacting element(s) gains more oxygen and has a greater oxidation state. Give an a ccount of the tuition of chemical compounds for use in explosives. Describe the advantages of each new chemical explosive over its predecessors, and name how the explosives were adapted to make them safer and more effective. 9 The very first uncovering of an explosive chemical compound was unintended. In 1846 Dr Christian Schi nobein accidentally spil lead concentrated sulphuric and nitric acids he quickly cleaned the contaminated area with an proscenium wall made of cotton.Knowing that the apron would soon be destroyed by the acids, he rinsed it out with peeing and hung it up to dry in front of the fire. Moments later the cloth burst into flames. Dr Schi nobein was not aware that he had discovered gun cotton otherwise known as Cellulose Nitrate or Nitrocellulose. From 1860s onwards the armament began investigating the possibilities of cellulose nitrate as a supergrass-free gunpowder. Towards the end of the nineteenth century, black powder had been replaced as a propellant fo r military purposes by a smokeless powder based on cellulose nitrate.This center field catches fire very quickly and burns without lighting a fuse produces very little smoke and creates an impulsive impact. Therefore, explosive shells were replaced by cannon balls and bullets replaced musket balls. This smokeless powder used by the British force is called cordite and was invented in 1880s. It consists of Cellulose Trinitrate and Glycerol Trinitrate amongst other substances. This substance catches fire very easily and burns quickly. The powder was transform into a jelly-like substance by adding an organic solvent propanone.This smokeless powder is now used planetary as a military propellant. (253 Words) In 1847 an Italian scientist, Ascanio Sobrero was experimenting with concentrated acids. He combined together nitric, sulphuric acids with glycerine. The new substance organise was a yellowish oil. He had discovered Nitroglycerine. He experimented with a petite sample and make t hat was extremely unstable. Its behaviour was unpredictable. It could be stir upd by the touch of a feather. Immanuel Nobel and his son Alfred Nobel from Sweden were answerable for controlling Nitroglycerine.Nobel made a deliberate explosion by mixing Nitroglycerine with (kieselguhr) which is a silicon oxide based mineral. He made a paste which could be shaped into rods. These would only explode when they are intentionally detonated. These are the very first safe high explosives. Nobel certain even safer ways to detonate these explosives. He found out that the most reliable and effective way to set off trinitroglycerin was to use gnomish quantities of gunpowder. He also invented the first percussion cap that gives out a small explosion when it is given a sharp impact.The caps were filled with a compound known as rail of mercury Hg(CNO)2. This substance is very sensitive that even a finger tap can cause it to detonate. This ignites the gunpowder or other explosives. In 1867 Nob el patented his dynamite. It was called Dynamite No 1. He soon realised that very effective mixtures could be made by replacing the inert kieselguhr by a substance that would itself burn or explode. He combined nitroglycerin with charcoal, barium nitrate and sulphur which led a new explosive product in 1869. It was called Dynamite No 2.This product was suitable for use in quarries and coal mines. Nobel patented another explosive product in 1875. He added 7 to 8 per cent of collodion (nitrated cellulose) to warm nitroglycerine forming a stiff jelly-like substance known as blasting gelatine. This product proved to be more powerful explosive than dynamite, because both nitroglycerine and collodion were explosive. During the Second World War, trinitrotoluene (trinitrotoluene) was developed. TNT contains nitro groups (NO2). It doesnt react with metals therefore can be used in metal containers to produce bombs.TNT causes headaches, anaemia and skin irritation. Subsequently, workers in fa ctories often suffered health problems. (280 Words) Discuss, with reference to high and low explosives, the ideal features of an explosive reaction, explaining, with examples, how chemical reactions produce energy and how they cause increase in pressure. 6 Nitroglycerine is acknowledged as a high explosive. It produces a large volume of hot gas. Its decomposition only takes microseconds at a pressure of 275 000 atmospheres. Black Powder and Cellulose Nitrate are considered as low explosives. They produce a large volume of hot gas.The decomposition takes millisecond at a pressure of 6000 atmospheres. An ideal explosive reaction essential take place very quickly. It must be an exothermic reaction where heat is given out. The products formed must mainly be hot gases produced in a confined space. This leads to a big come near in pressure which is the main cause of the explosion. An equation for explosion of nitroglycerine C3H5N3O9 (l) 3CO2 (g) + 21/2H2O (g) +11/2N2 (g) + 1/4O2(g) 1 m ol of liquid 7. 25 moles of gas No oxygen supply from air was infallible for the reaction. The exact products are based on the actual explosion.In an oxidation reaction oxides of nitrogen such as (NO and NO2) may be produced. The amount of heat energy released from a nitroglycerine explosion is 6275 KJ kgi 1. The increase in pressure will produce greater energy from the explosion. Describe how UK methods of manufacture of propanone rent changed since the beginning of the First World War. 3 Before the war propanone was manufactured by dry distillation of wood in a process that excluded air. This method was very inefficient. In 1914 a Russian chemist, Chaim Weizmann, developed a new process that produced propane by bacterial fermentation of starch in maize.This process was undefendable of producing 30 000 tonne. After the war propanone was manufactured from propan-2-ol by passing the vapour over a copper catalyst at 500i C and 400kPa. Propanone was produced from propene, a product of catalytic cracking of boisterous oil fractions. (230 Words) Discuss how attitudes to health and safety in chemical research and industrial chemistry look at changed over time. Use examples from the history of development and manufactures of explosives and medicines. 4 The discovery of cellulose nitrate was a hazard of health and safety.The discovery of nitroglycerine was another major hazard as it its behaviour was very unpredictable. Its discoverer Ascanio Sobrero was badly disfigure as a result of an unexpected explosion that spattered glass fragments into his hands and face. He verbalize victims killed during nitroglycerine explosions He was ashamed to be the inventor of such a deadly explosive. In Nobels nitroglycerine factory, there was an explosion that killed his young brother Emil and another chemist. However test on animals showed that nitroglycerine causes pitch vessels of the brain and heart to flow with blood.Nitroglycerine was considered a possible treatment. N itroglycerine is effective for treating angina pectoris intensive pain in heart. A medicine known as amyl nitrate similar to nitroglycerine are used as treatments to this day. (110 Words) OCR-AS Chemistry (Salters) Open-Book Paper (2005) 2852/01 1 Name Mohammad Ahmed Candidate No. 9023 Show poke only The above preview is unformatted text This student written piece of work is one of many another(prenominal) that can be found in our GCSE Patterns of Behaviour section.