Free Enthalpy Change Essays and Papers

Investigating Enthalpy Change During this investigation I will be burning a selection of different alcohol's to heat a container of water. I will be burning four alcohols, methanol, ethanol, propanol and butanol. The aim of the experiment is to find out how much energy is produced when these alcohols are burnt and to see if there's a relation between how many, and how strong the bonds are between molecules in the elements burnt, and how quickly the water is heated up. To put it simply, we

Analysis and Results of Enthalpy Change ALCOHOL AVERAGE MASS BURNT (G) METHANOL 1.54 ETHANOL 1.02 PROPAN-1-OL 0.77 BUTAN-1-OL 0.69 PENTAN-1-OL 0.55 HEXAN-1-OL 0.52 Following the gathering of results, the enthalpy change of combustion of the alcohols was calculated using the equation from page 2: Energy Transferred = Mass of water x Temperature rise x specific heat capacity (4.17) Now to calculate the enthalpy change of combustion, the following

Enthalpy Changes of Combustion of Different Alcohols Aim: The aim of this experiment is to find out how the enthalpy change (total energy released when the alcohols are completely combusted in a plentiful supply of air) for 5 different alcohols is affected by the number of carbon atoms in the alcohol and other factors contributing to the molecular structure. Prediction: I predict that as the amount of carbon atoms in the alcohol increases, the higher the enthalpy of combustion will

The Enthalpy Change of Different Alcohols My aim is to compare the enthalpy change of combustion of different alcohols in relation to the structure of each molecule. The enthalpy change of combustion of a fuel is a measure of the energy transferred when one mole of the fuel burns completely. In a chemical reaction, bonds must either be made or broken, this involves an enthalpy change. The formation of bonds is exothermic, energy is lost to the surrounding; on the other hand, breaking bonds

Use of Enthalpy Changes of Metal Reactions The problem: The problem that I will investigate is how to use enthalpy changes of metal reactions to experimentally test the reactivity series of common metals. Therefore the area that I am looking at is reactions involving metals and the heat energy that is evolved when these take place. In brief the reactivity series of metals is a list in which metals are ranked according to their reactivity, from the most reactive metals (such as Pottassium)

Determining the Enthalpy Change of A Reaction If Calcium Carbonate, CaCO3, is heated it decomposes into Calcium Oxide, CaO and Carbon Dioxide, CO2. [IMAGE]CaCO3 CaO + CO2 The aim of this experiment is to determine the enthalpy change of this reaction. To do this I will react both Calcium Carbonate and Calcium Oxide, separately, with 2mol dm-3 Hydrochloric Acid, HCl. By recording the temperature changes in each reaction, and using Hess's Cycle, I will be able to work out the enthalpy change

Comparing the enthalpy changes of combustion of different alcohols. What are the effects of alcohol? ===================== Alcohol is the common family name for the hydrocarbon group alkanol. At least one of the hydrogen groups is replaced by an OH group. They are all organic compounds. The general formulas for the alcohols are: CnH(2 n +1 ) OH Where n represents a number. The first and simplest member of the alkanol family is methanol. Its molecular formula is CH3OH. You can now see that each member

Determination of the Enthalpy Change of a Reaction Determine the enthalpy change of the thermal decomposition of calcium carbonate by an indirect method based on Hess' law. Determination of the Enthalpy Change of a Reaction Determine the enthalpy change of the thermal decomposition of calcium carbonate by an indirect method based on Hess' law. Using the proposed method of obtaining results, these values were gathered: Reaction 1: CaCO3(s) + 2HCl(aq) CaCl2(aq) + CO2(g) + H2O(l) GRAPH ¼ in

Comparing the Enthalpy Changes of Combustion of Different Alcohols Aim: I will find the enthalpy change of combustion of a number of alcohols so that I can investigate how and why enthalpy change is affected by molecular structure of the alcohol. Outline: I will use Methanol, Ethanol, Propanol and Butanol in the experiment. I will use these four because they should give me clear results, and they range from short chained to long-chained hydrocarbons, so patterns should be easy to

The change in enthalpy for the combustion of magnesium metal Abstract ======== Hess’s law of heat summation states that the value of DH for a reaction is the same whether it occurs directly or as a series of steps. This principle was used to determine the change in enthalpy for a highly exothermic reaction, the combustion of magnesium metal. Enthalpy changes for the reactions of Mg in HCl (aq) and MgO (s) in HCl (aq) were determined experimentally, then added to that for the combustion of hydrogen