Investigating Heat Of Combustion And The Safety Of Three Alcohols

Combustion Reaction: A chemical reaction between a fuel and an oxidizing agent that produces heat.

Fuels are an important component of everyday life in the world today. A fuel is any material that stores potential energy that is released into usable energy for work or released as heat (Wikipedia, fuels, 2015). When under combustion, the covalent bonds in the fuel are broken and release energy through exothermic reactions. Alcohols are a type of fuel that is safer and more abundant to burn. An alcohol is any organic compound where a hydroxyl is chemically bound to a saturated carbon atom where there are only single bonds in the molecule (Wikipedia, saturation, 2015; Wikipedia, alcohol, 2015). Alcohols can either be straight-chained or branch chained, each being an alkane. A carbon atom joined onto at most two other carbon atoms is a straight chain, whereas a branch chained alcohol is one where the empirical formula is identical to that of a straight chain, however the structure is variant or where at least one carbon atom is joined onto more than two carbon atoms. This difference in structures results in the former having a higher boiling point. The straight chain molecules can align more efficiently with each other and hence have higher intermolecular forces or Van der Waals forces (gcsescience.com, Products from Oil, 2015).

In a combustion reaction, a compound or element reacts with oxygen, releasing a large amount of energy in the form of light and heat.

Fuel is usually consistent of octane, ethyl benzene, Trimethylpentane, toluene, and brutane. The reactions of 3.51kg of oxygen to one kilogram of fuel causes the production of 1.42kg pf water and 3.09kg of carbon dioxide. Simply written out, it would form an equation similar to C8H18+O2+CO2+H2O —> CO2+H2O. Dismally, this doesn’t work as a proper equation, as one would find it impossible to balance out. The balanced equation would be closer to C8H18+O2 —> CO2+H2O. Now that one is able to balance the equation, we’ll multiply the carbon dioxide and water by eight and nine respectively. Now there are too many oxygen on the right side of the equation (product). We move to the left side of the equation (reactant) and change the O2 to 25/2O2. Balanced, the equation is C8H18+25/2O2 —> 8CO2+9H2O. In terms of heat through energy, this equation can be converted to [(8 x -393.5) + 9 x -241.8)] - 250.1. What this means is for each time the reactant produces the CO2+H2O mixture, -5270kj of energy are produced.

These experiments were established to find which fuel, out of Pentane, Propan-1-ol and Propan-2-ol would be the most suitable to take on a camping trip to cook with.

Spontaneous combustion An occurrence where a material self-heats to its piloted ignition temperature, then ignites.

Baking Soda - This common ingredient, when heated produces Carbon Dioxide gas. Since the fire would be getting carbon dioxide, the amount of oxygen the fire would be receiving would be limited resulting in the fire being stopped as oxygen is one thing that is required for combustion.

Purpose of this lab was to see which accelerants best burned the house and the different stages of burning. The accelerant that our group used was alcohol. It burned faster than the other accelerants. Other groups used accelerants such as: acetone, gasoline, and hand sanitizer. The acetone burned quickly and almost evaporated instantly. The hand sanitizer and gasoline were both quicker in the spread of the fire. Though alcohol and gasoline ignited quicker. For our group flashover only lasted eight seconds. Flashover happened so quick because there was complete combustion. You could see the flash over occur when the whole house was engulfed in flames as well as the whoosh sound. There was no conduction that we could physically touch unless we

For this experiment we where trying to find out what are some of the produces of combustion? To start out we made a list of possible products of combustion for a candle. The only thing that we really thought about was the carbon monoxide that is produced. For the experiment we took a candle, a 1000 mL and 500 mL beaker, cobalt chloride paper, and lighter. We first put the 1000 mL beaker over the candle, which we lighted with the light, then after the candle created a fog like form on the beaker. We stopped and right away rubbed the cobalt chloride paper over the fog, which was in the beaker and was caused by the water. Very shortly after the cobalt chloride paper turned from a blue into light pink color. After this we put water on the strip,

1-Hexanol has a chemical formula of CH3(CH2)5OH and a melting point of: -53 to -41 °C and a boiling point of: 155 to 159 °C The heat of combustion of 1-hexanol is 4638 kJ mol-1 and it has a combustion equation of 2C6H13OH(l) + 18O2(g) → 12CO2(g) +

This release of chemical potential energy gives off energy in the form of heat;( see Appendix A, figure 1) for diagram showing the release of exothermic energy during combustion. The amount of heat energy released during the chemical reaction of combustion is called enthalpy. Enthalpy can be calculated using the equation Enthalpy= H= E+pV(See Appendix A, figure 2) for variables(NASA 2015). Hydrocarbons of different sizes vary in their abilities to be heated.

Carbon Dioxide is generated primarily through the burning of fossil fuels, solid waste, trees and wood products. Deforestation and solid degradation also add carbon dioxide to the atmosphere. It negative effects can be reduced by forest growth, which takes it out of the atmosphere through photosynthesis.

Fuel combustion is the process of where fuel is burnt that releases heat and light which is an exothermic reaction meaning it releases heat. The fuel is a hydrocarbon, which reacts with oxygen to release energy however a small amount of heat energy is needed to start fuel combustion. The products to the reaction are carbon dioxide and water.

Smouldering is defined as a self-sustaining exothermic reaction in which the heat released by surface oxidation causes pyrolysis of the unaffected fuel adjacent to the reaction zone, which in turn yields a rigid char which will subsequently undergo surface oxidation citep{smith2006springer}. The initiation of furniture fires by weak heat sources, such as, a cigarette or a short-circuited wire, and the flaming combustion of biomass occurring in bushfires behind the flaming front are two common examples of smouldering combustion citep{rein2009smouldering}.\

The aim of this experiment was to test the heat of combustion over a period of time, and the energy required to combust alcohols with different carbon chain levels. It was hypothesised that the higher the carbon chain of the alcohol present, the faster the heat of combustion will occur. Meaning more energy will be released for a higher carbon chain. After calculating the results from the experiment it was found that the hypothesis was partially supported. The reasoning for this is as the alcohol that posses a higher carbon chain, generally increased there reaction rates. However there were a few exceptions to this rule.