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 nigh exothermicPredictionI predict that the most heat devoted egress per mole burned would be by propyl alcohol because the size of the alcohol molecules might increase withheat. inebriants produce heat when they burn in oxygen or air. Theamount of heat produced per mole of alcohol depart be proportional tothe amount of air present. Full combustion should hark back twoproducts only carbon dioxide and water vapour.HypothesisWithin a molecule there are bond energies that are holding the atomstogether. When the displace combusts a chemical reaction takes place, thisbreaks the bonds, this requires energy, and makes new bonds this givesout energy. The energy differences mingled with the two tell us how some(prenominal)energy was given out or taken in. We tail end show this on a graph. Alcoholparticles will break their bonds when they mix with oxygen. This isknown as exothermic reaction. stewing points will be increased becauseenergy is needed bonds can be potpourried and broken. Breaking bonds needless energy than is needed to form bonds - exothermic reaction. Biggermolecules use high energy to be broken. methyl alcohol and Ethanol havedifferences as Methanol melts at a high temperature and boils at alower temperature than Ethanol. Higher alcohols which include butyl alcoholand Propanol have a higher molecular weight and this is why Butanol isused in perfumes. Ethanol, which is sugar based, with its low freezingpoint, has a specialized use as antifreeze for cars and other vehicles. GRAPHTripod Matches GogglesMethod - To mother with, I choose one out of the four differentalcohols. 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 l ight the spirit burner and stir the water with thethermometer constantly. When the temperature has rise to 30C, Iquickly place the top back on the spirit burner. Now I re-weigh thealcohol. o find out how much alcohol has been burned I subtract thefinishing mass from the starting line mass.Fair TestI will try my best to conserve this experiment fair. All the variablesmust be controlled. These are as follows -The outdo reading has to be on zero before weighing the spirit burner