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    Can anyone show me how to work out this chemistry problem, I’m pulling my hair out over it as we haven’t done it in class.
    A pressurised gas canister contains liquid hydrogen, inside the canister there is a distance of 4 x 10 -8 m3 between the hydrogen molecules. Calculate the ratio of the distance between hydrogen molecules to the width of a single hydrogen atom (the width of a hydrogen atom is 5 x 10-11m)Any help would be gratefully received, thanks, Noah
    My TSRForumsGCSEA-levelApplying to uniUniversityCareers & jobsRelationships & healthNews & entertainmentStudent financeHome > GCSE study tools > Chemistry > Chemistry Unit 1 Chemistry Unit 15.0/ 5ChemistryC1GCSEOCRCreated by: Gracieee123Created on: 21-05-16 11:28Edit a CopyView mindmap Chemistry 1Crude OilCrude oil, natural gas coal. Formed extremely slow. They are finite (limited supply) and non renewable (using them up faster than being formed so eventually run out)Crude oilTrapped in Eaths crust. Released by hole being drilled through rock. Oil has to be under pressure to flow out.When extracted is thick, black sticky liquid which is transported to a refinert through pipeline.Toxic oil can coat feathers of sea birds. Oil wash ashore and damage beaches which leads to a big clean up. Detergents used to disperse oil however toxic to widelifeFractional DistillationCrude oil is split into fractions containing similar sized molecules using fractional distillation. The oil is heated until it vaporises. It then passes up a tall tower that is hot at the bottom but cool at the top. As the vapour passes up this tower the molecules cool and condensehydrocarbonsSmall hydrocarbon- Small forces of attraction, easy to break by heating, volatile substance, low boiling pointLong hydrocarbon- large force of attraction, difficult to break by heating, think viscous liquid, higher melting pointCrackingConverts large alkane molecules into smaller more useful alkane/alkene molecules. Smaller alkane molecules blended to make petrol (huge demand).Needs catalyst and high temperature.Carbon FuelsChoosing a fuelEnergy, Value, Cost, Availability, Toxicity, Ease of use, Storage, PollutionCombustionComplete= Methane + Oxygen ? Carbon dioxide + WaterIncomplete= Methane + Oxygen ? Carbon monoxide + WaterVery little oxygen= Methane+ Oxygen ? Carbon+ WaterClean AirChanging atmosphereEarliest atmosphere contained ammonia and carbon dioxide. This came from inside Earth and was released through action of volvanoesTemperature fell, water vapour in atmosphere condensed to form ocean+ seaEvolution of plants meant photosynthe-sis started reduce amount carbon dioxide + increase oxygen in atmosphereClean air, 78% nitrogen 21% Oxygen 1% other gases including 0.035% carbon dioxidePollutionPollution gasses formed by Burning fossil fuels and incomplete combustion of car engineCar exhausts produce Carbon monoxide, Nitrogen dioxide(leads to acid rain), unburned hydrocarbons (creates smog)Oxides of nitrogen produces acid rain and photochemical smogAerosols produce CFCs (damage ozone layer)A way to removie carbon monoxide from car exhaust is to fit a catalytic converts. It causes the carbon monoxide to react producing carbon dioxidecarbon monoxide+ nitrogen oxide ? nitrogen+ carbon dioxideAcid RainCoal/Oil burned sulphur impurities produce sulphur dioxide. This plus nitrogen dioxide dissolves in water to produce acid rain. Acid rain can erode stonework and corrode metals, kill plants, make rivers acidic and kill aquatic lifeHuman influences on atmosphereExcessive burning of fossil fuels is increasing the amount of carbon dioxide in atmosphere. Deforestation on large areas of the Earth surface means amount of photosynthesis is reduces from the atmosphere.Making polymersAlkanes and AlkenesAlkanes have a single covalent bond and are saturated .With bromine water is colourless (have max number of hydrocarbon atoms per carbon atom in molecule) Alkenes have double covalent bond and are unsaturated. With bromine water is orange (carbon atom is not bonded to max number of hydrogen atoms)PolymerisationAlkenes made by cracking can be used as monomers. These are small molecules that can be reacted to make polymers. Alkenes are good at joining together and when they dont produce another substance it is polymerisationThe process needs high pressure and catalyst.Addition PolymerisationInvolves reaction of any unsaturated monomer molecules eg alkenes to form a saturated polymerDesigner PolymersPolymer plastic propertiesEasily molded, Waterproof, Electrical insulator, Non- biodegradable, Lightweight, Flexible, Can be printed on, Unreactive.Can be coloured, Heat insulator, Transparent, ToughOutdoor clothing- Nylon. Because its light weight, tough, waterproof (dosnt let vapour escape so it could be uncomfortable to wear is person gets hot and perspire.)Gore-tex is a breathable material with all advantages of nylon but allows water vapour to escape but prevents rain from getting in. It has a membrane of polyurethane sandwiched between 2 layers of nylon fibres, The polyurethane has tiny holes that allow vapour to pass through but that are too small to let liquid vapour though.The structure of plastics is that the consist of a tangles mass of very long chain molecules in which atoms are held together by strong covalent bonds. Plastics that have weak forces between polymer molecules have low melting points and can be stretched easily as the polymer molecules can slide over one another. Plastics that have strong forces between the molecules have high melting points, rigid+ can't be streachedDisposal of plasticsLandfills sites. Problem because most plastics are non-biodegradable. Therefore micro-organisms have no effect on them and will not decompose+ rot away. Waste of landBurning plastics. Produce air pollution+waste valuable resoucres. Produce carbon dioxide (greenhouse effect) leads to global warmingRecycling plastic. Prevents resources being wasted. However different types of plastic need to be recycled separately. Therefore time consuming.Cooking + Food AdditivesCooking foodCauses a chemical reaction to occur, (new substances formed from old ones, change in mass, energy change, rise/fall in temperatureEggs and meat contain protein, the protein molecules change shape shape when they are heated denaturing. Therefore texture changes.Potatoes and other vegetables are plants and their cells have rigid cell walks. During cooking the heat breaks down this cell wall, starch is released and it becomes softer. The starch grains swell up and spread out, this makes the potato is easier to digestBaking PowderContains sodium hydrogen carbonate. When heated it decomposes to make sodium carbonate and water and carbon dioxide gas is given off. Sodium hydrogen carbonate? sodium carbonate+ water+carbon dioxideAdditivesAntioxidants, material that stops food reacting with oxygen in the air. Food colouring, improve appearance in food. Flavour enhances, bring out flavour. Emulsifiers, help mix ingredients which would normally separate,EmulsifiersMolecules in a emulsifier have 2 ends. 1 like to be in water (hydrophilic) and the other end likes to be in oil (hydrophobic). Emulsifier join droplets together and keeps them mixed. The hydrophilic end of the water emulsifier molecule bonds to the polar water molecules. The hydrophobic end of emulsifier molecule bonds to non-polar oil moleculesSmellsPerfumesMust smell nice, evaporate easily (travel up nose), non toxic, not irritate, not dissolve in water, not react with water (react with perspiration)EstersUsed as synthetic perfumes. Made by reacting alcohol with organic acid. This produces an ester and water.Perfumes are volatile (evaporate easily). Molecules in a drop of perfume are held together by a weak intermolecular forces of attraction. The molecules that escape have lots of energy and easily overcome the weak attraction to the other molecules in the liquidWater doesn't dissolve nail varnish because the attraction between water molecules is stronger that the attraction between water molecules and the particles in nail varnish. Also the attraction between particles in nail varnish is stronger than the attraction between water molecules and particles in nail varnishPaintsSpecial mixture of different material and that is called a colloid. In a colloid, fine solid particles are well dispersed with liquid particles but don't dissolve.Mixture of Pigment(substance give paint colour), binding medium (oil sticks pigment to surface its being painted onto) Solvent (dissolves thick binding medium+makes it thinner+easier to coat surfacePaint coat surface with thin layer and solvent evaporates away as paint dries. Solvent in emulsion paint is water. In oil-based paints the pigment is dispersed in oil (binding medium).Thermochromic pigments. Can be used in cups+kettles to warn when hot. Bath toys to show water is correct temperature for baby. Phosphorescent pigments glow in dark. To increase range of therochromuuc pigments they can be mixed with ordinary pigments in acrylic paintsParticle size of solids in colloid must be very small so they stay scattered throughout the mixture. If particles too big they would start to settle down to bottom.Oil based paint dries in 2 stages. (1) Solvent evaporates away (2) Oil-binding medium reacts with oxygen in the air as it dries to form a hard layer. This is oxidation reactionChemistry 1Crude Oil Crude oil, natural gas coal. Formed extremely slow. They are finite (limited supply) and non renewable (using them up faster than being formed so eventually run out)Crude oilTrapped in Eaths crust. Released by hole being drilled through rock. Oil has to be under pressure to flow out. When extracted is thick, black sticky liquid which is transported to a refinert through pipeline. Toxic oil can coat feathers of sea birds. Oil wash ashore and damage beaches which leads to a big clean up. Detergents used to disperse oil however toxic to widelifeFractional DistillationCrude oil is split into fractions containing similar sized molecules using fractional distillation. The oil is heated until it vaporises. It then passes up a tall tower that is hot at the bottom but cool at the top. As the vapour passes up this tower the molecules cool and condensehydrocarbonsSmall hydrocarbon- Small forces of attraction, easy to break by heating, volatile substance, low boiling pointLong hydrocarbon- large force of attraction, difficult to break by heating, think viscous liquid, higher melting pointCrackingConverts large alkane molecules into smaller more useful alkane/alkene molecules. Smaller alkane molecules blended to make petrol (huge demand).Needs catalyst and high temperature. Carbon FuelsChoosing a fuelEnergy, Value, Cost, Availability, Toxicity, Ease of use, Storage, Pollution CombustionComplete= Methane + Oxygen ? Carbon dioxide + Water Incomplete= Methane + Oxygen ? Carbon monoxide + WaterVery little oxygen= Methane+ Oxygen ? Carbon+ WaterClean AirChanging atmosphereEarliest atmosphere contained ammonia and carbon dioxide. This came from inside Earth and was released through action of volvanoesTemperature fell, water vapour in atmosphere condensed to form ocean+ seaEvolution of plants meant photosynthe-sis started reduce amount carbon dioxide + increase oxygen in atmosphereClean air, 78% nitrogen 21% Oxygen 1% other gases including 0.035% carbon dioxidePollutionPollution gasses formed by Burning fossil fuels and incomplete combustion of car engineCar exhausts produce Carbon monoxide, Nitrogen dioxide(leads to acid rain), unburned hydrocarbons (creates smog)Oxides of nitrogen produces acid rain and photochemical smogAerosols produce CFCs (damage ozone layer)A way to removie carbon monoxide from car exhaust is to fit a catalytic converts. It causes the carbon monoxide to react producing carbon dioxideAcid RainCoal/Oil burned sulphur impurities produce sulphur dioxide. This plus nitrogen dioxide dissolves in water to produce acid rain. Acid rain can erode stonework and corrode metals, kill plants, make rivers acidic and kill aquatic lifeHuman influences on atmosphereExcessive burning of fossil fuels is increasing the amount of carbon dioxide in atmosphere. Deforestation on large areas of the Earth surface means amount of photosynthesis is reduces from the atmosphere. carbon monoxide+ nitrogen oxide ? nitrogen+ carbon dioxideMaking polymersAlkanes and AlkenesAlkanes have a single covalent bond and are saturated .With bromine water is colourless (have max number of hydrocarbon atoms per carbon atom in molecule) Alkenes have double covalent bond and are unsaturated. With bromine water is orange (carbon atom is not bonded to max number of hydrogen atoms)PolymerisationAlkenes made by cracking can be used as monomers. These are small molecules that can be reacted to make polymers. Alkenes are good at joining together and when they dont produce another substance it is polymerisationThe process needs high pressure and catalyst. Addition Polymerisation Involves reaction of any unsaturated monomer molecules eg alkenes to form a saturated polymerDesigner PolymersPolymer plastic propertiesEasily molded, Waterproof, Electrical insulator, Non- biodegradable, Lightweight, Flexible, Can be printed on, Unreactive.Can be coloured, Heat insulator, Transparent, ToughOutdoor clothing- Nylon. Because its light weight, tough, waterproof (dosnt let vapour escape so it could be uncomfortable to wear is person gets hot and perspire.)Gore-tex is a breathable material with all advantages of nylon but allows water vapour to escape but prevents rain from getting in. It has a membrane of polyurethane sandwiched between 2 layers of nylon fibres, The polyurethane has tiny holes that allow vapour to pass through but that are too small to let liquid vapour though. The structure of plastics is that the consist of a tangles mass of very long chain molecules in which atoms are held together by strong covalent bonds. Plastics that have weak forces between polymer molecules have low melting points and can be stretched easily as the polymer molecules can slide over one another. Plastics that have strong forces between the molecules have high melting points, rigid+ can't be streachedDisposal of plastics Landfills sites. Problem because most plastics are non-biodegradable. Therefore micro-organisms have no effect on them and will not decompose+ rot away. Waste of landBurning plastics. Produce air pollution+waste valuable resoucres. Produce carbon dioxide (greenhouse effect) leads to global warmingRecycling plastic. Prevents resources being wasted. However different types of plastic need to be recycled separately. Therefore time consuming.Cooking + Food AdditivesCooking foodCauses a chemical reaction to occur, (new substances formed from old ones, change in mass, energy change, rise/fall in temperature Eggs and meat contain protein, the protein molecules change shape shape when they are heated denaturing. Therefore texture changes. Potatoes and other vegetables are plants and their cells have rigid cell walks. During cooking the heat breaks down this cell wall, starch is released and it becomes softer. The starch grains swell up and spread out, this makes the potato is easier to digestBaking PowderContains sodium hydrogen carbonate. When heated it decomposes to make sodium carbonate and water and carbon dioxide gas is given off. Sodium hydrogen carbonate? sodium carbonate+ water+carbon dioxideAdditivesAntioxidants, material that stops food reacting with oxygen in the air. Food colouring, improve appearance in food. Flavour enhances, bring out flavour. Emulsifiers, help mix ingredients which would normally separate, EmulsifiersMolecules in a emulsifier have 2 ends. 1 like to be in water (hydrophilic) and the other end likes to be in oil (hydrophobic). Emulsifier join droplets together and keeps them mixed. The hydrophilic end of the water emulsifier molecule bonds to the polar water molecules. The hydrophobic end of emulsifier molecule bonds to non-polar oil moleculesSmellsPerfumesMust smell nice, evaporate easily (travel up nose), non toxic, not irritate, not dissolve in water, not react with water (react with perspiration)EstersUsed as synthetic perfumes. Made by reacting alcohol with organic acid. This produces an ester and water. Perfumes are volatile (evaporate easily). Molecules in a drop of perfume are held together by a weak intermolecular forces of attraction. The molecules that escape have lots of energy and easily overcome the weak attraction to the other molecules in the liquidWater doesn't dissolve nail varnish because the attraction between water molecules is stronger that the attraction between water molecules and the particles in nail varnish. Also the attraction between particles in nail varnish is stronger than the attraction between water molecules and particles in nail varnish PaintsSpecial mixture of different material and that is called a colloid. In a colloid, fine solid particles are well dispersed with liquid particles but don't dissolve. Mixture of Pigment(substance give paint colour), binding medium (oil sticks pigment to surface its being painted onto) Solvent (dissolves thick binding medium+makes it thinner+easier to coat surfacePaint coat surface with thin layer and solvent evaporates away as paint dries. Solvent in emulsion paint is water. In oil-based paints the pigment is dispersed in oil (binding medium). Thermochromic pigments. Can be used in cups+kettles to warn when hot. Bath toys to show water is correct temperature for baby. Phosphorescent pigments glow in dark. To increase range of therochromuuc pigments they can be mixed with ordinary pigments in acrylic paintsParticle size of solids in colloid must be very small so they stay scattered throughout the mixture. If particles too big they would start to settle down to bottom. Oil based paint dries in 2 stages. (1) Solvent evaporates away (2) Oil-binding medium reacts with oxygen in the air as it dries to form a hard layer. This is oxidation reactionRate this resource: 0/ 5See similar resourcesPrintable PDFSave to favouritesShare: CommentsInNeedOfHelpSun 22nd May, 2016 @ 18:00This was so helpful thank you!!!Post a commentBody​Post my comment Similar Chemistry resources:chemistry3.0/ 5Chemistry0.0/ 5Chemistry3.0/ 5Chemistry3.0/ 5Chemistry0.0/ 5Chemistry3.0/ 5Chemistry3.0/ 5Chemistry4.5/ 5Chemistry2.0/ 5Chemistry4.5/ 5See all Chemistry resources »See all C1 resources »ShortcutsMy TSR Forums GCSE A-level Applying to uni University Careers & jobs Relationships & health News & entertainment Student finance Win Get StartedFind members Who's online Today's posts Unanswered posts Polls University Connect Photo albums Using TSRCommunity guidelines Cookies and online safety TSR Support Team News, help and feedback Terms and conditions Privacy policy FAQs and help TSR GroupMarked by Teachers Get Revising InfoAbout The Student Room Advertise Contact Connect with TSRFollow TSR on Twitter Find us on Facebook © Copyright The Student Room 2016 all rights reserved The Student Room, Get Revising and Marked by Teachers are trading names of The Student Room Group Ltd.Register Number: 04666380 (England and Wales), VAT No. 806 8067 22Registered Office: International House, Queens Road, Brighton, BN1 3XE
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    Could you shorten this a bit? :laugh::laugh:
 
 
 
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