An investigation to determine which of four alcohols is the most exothermic :: GCSE Chemistry Coursework Investigation

An investigation to determine which of four alcoholic drinks is the most exothermicPredictionI holler that the most heating system given out per mole burned would be byPropanol beca expenditure the size of the alcohol molecules might increase withheat. Alcohols produce heat when they burn in oxygen or air. Theamount of heat produced per mole of alcohol will be proportional tothe amount of air present. Full burn should generate twoproducts only carbon dioxide and water vapour.HypothesisWithin a molecule there are bond energies that are holding the atomstogether. When the provoke combusts a chemical reaction takes place, thisbreaks the bonds, this requires energy, and makes new bonds this givesout energy. The energy differences between the two tell us how muchenergy was given out or taken in. We can show this on a graph. Alcoholparticles will break their bonds when they mix with oxygen. This isknown as exothermic reaction. Boiling points will be increased becauseenergy is needed b onds can be formed and broken. Breaking bonds needless energy than is needed to form bonds - exothermic reaction. Biggermolecules use high energy to be broken. Methanol and Ethanol havedifferences as Methanol melts at a higher temperature and boils at alower temperature than Ethanol. high alcohols which include Butanoland Propanol have a higher molecular weight and this is why Butanol isused in perfumes. Ethanol, which is sugar based, with its low freezepoint, has a specific use as antifreeze for cars and other vehicles. GRAPHTripod Matches GogglesMethod - To begin with, I choose one out of the four oppositealcohols. I weigh beforehand in the spirit burner. This is so I cancalculate the mass which is lost in each alcohol. The spirit burnerand alcohol which I am using is on a brick under a tripod. On thetripod I place a clay pipe triangle which holds a beaker containing100ml of water. I light the spirit burner and stir the water with thethermometer con stantly. When the temperature has risen to 30C, Iquickly place the top back on the spirit burner. immediately I re-weigh thealcohol. o find out how much alcohol has been burned I subtract thefinishing mass from the starting mass.Fair TestI will try my best to keep this experiment fair. All the variablesmust be controlled. These are as follows -The scale reading has to be on slide fastener before weighing the spirit burner