Experimental Molar Enthalpy of Neutralization for Sodium Hydroxide Solution Essay

1. For information regarding the problem, prediction, materials and procedure, please visit attachedMeasurements tabulate for Molar erupt content of Neutralization for Sodium Hydroxide Solution importInstrument UsedMeasurementSodium hydroxide100mL graduated piston chamber (0.2mL)50.0mLSulfuric acid100mL graduated cylinder (0.2mL)30.0mLTemperature of sodium hydroxide dissolverThermometer (0.2C)26.0CTemperature of the sulfuric acidThermometer (0.2C)24.0CFinal temperature reached by originThermometer (0.2C)34.5CInitial and Final Temperatures of SolutionsTemperature of sodium hydroxide solving (0.2C)26.0CTemperature of the sulfuric acid (0.2C)24.0CFinal temperature reached by solution (0.2C)34.5CNeutralization Reaction Taking PlacePre-Lab Calculations Volume of Sulfuric i direct NeededAverage Initial Temperature of Solutions CalculationExperimental Molar Enthalpy of Neutralization for Sodium Hydroxide Solution CalculationSolution1. The observational bomber henry of neutrali zation for sodium hydroxide solution was put together to be-643.3KJ/mol.Calculation of Uncertainties34.50.2C 25.00.2C=9.50.2C500.2mL + 300.2mL=800.2mL9.5 0.4C = 4.210%80 0.4mL = 0.5%50 0.2mL = 0.4%=5.11%=5.1%Percent Difference closure done a pre- lab calculation the amount of sulfuric acid solution needed was found to be 30.0m0.2mL. Using this information, a calorimetric lab was conducted to find the molar henry of neutralization for the sodium hydroxide solution. Through molar enthalpy calculations, the tasteal molar enthalpy of neutralization for the sodium hydroxide solution was found to be -64.03.3KJ/mol however, the theory-based (actual) molar enthalpy of neutralization for the sodium hydroxide solution is -57KJ/mol. In different words the experimental enthalpy counter flip-flop was -64.03.3KJ and the theoretical (actual) enthalpy salmagundi was -57KJ. This as a contribute p magnetic poleuced a 12% difference. The various errors forget be analyzed in the evaluation .EvaluationAs discussed earlier in the conclusion, the experimental convert in enthalpy is greater than the theoretical (actual) metamorphose in enthalpy. This result is quite rare. In general, a typical result for the experimental enthalpy change should yield an outcome lower than the theoretical (actual) value (the causa for this ordain be discussed later in the conclusion) however, this was not the case in this lab. There are a variety of reasons why the experimental enthalpy change for this lab was greater than the theoretical (actual) enthalpy change.In general, the main reason for the result seen in this lab is receivable to the nature of the calorimeter. Due to the fact the calorimeter is an isolated surroundings on that point is no possible method to determine when the response is blast. As a result, the answer may have been occurring in a turn area. With an increased slow-wittedness of reactants in one area, the rate of the reaction increases along with the temp erature in the concentrated area. When this foment transfers to the thermometer, it stimulates an increased change in enthalpy. Norm whollyy, the concentration of reactants would be less, as they are not in a concentrated area. This would therefore cause a lower temperature increase because there is a smaller misadventure the particles get out collide. As a result, the change in enthalpy in a normal situation would be much lower than if the reactants were all concentrated in one area.In saying that, it is possible at bottom this lab the reactants were concentrated in one area causing the experimental change in enthalpy to be quite large. Because it is impossible to see into the calorimeter to see if the reaction is concentrated or when the reaction is complete the reactants could easy have been concentrated in one area. Furthermore, by not cognise when the reaction is complete, the temperature might be measured too soon or too late causing inaccurate results. In general, bec ause the calorimeter is an isolated environment it results in the experiment having many errors because how the reaction is occurring and when the reaction is finished is unknown. A way to pooh-pooh this error is by inserting an electronic stirring rod to stir the reactants so they do not become concentrated in one area.Furthermore, another reason contributing to the large enthalpy change is the impurity of the substances used. As a result, because the substances are impure, they could have had a high concentration of reactants. With a higher concentration of reactants, the reaction rate allow increase and there will be a greater reaction than wanted. With a larger reaction at an increased rate, the final temperature of the solutions will spike higher than wanted generating a larger enthalpy change. As a result, this is a reason contributing to the large enthalpy change in this lab however, this reason is not very(prenominal) signifi dissolvet as the substances cannot be so impu re the concentration on the label is exceedingly different then the concentration found in the bottle (it is penal to put false information on chemical substances). As a result, the impurity of the substances cannot account for all the errors in this lab. Purifying the substances beforehand can easily eliminate this source of error.Moving on, there is another reason contributing to the large enthalpy change. The theoretical (actual) value given is obtained at SATP conditions however, when the following lab was conducted, the conditions were not at SATP. SATP conditions are at 100kPa and 25C. The conditions when the lab was conducted were at 101.9kPa and 25C.By increasing the pressure, the reaction rate is increased and more reactions take place. As a result of a larger quantity of reactions occurring at 101.9kPa than at the standard SATP conditions, there will be a greater change in enthalpy at 101.9kPa. This as a result, contributes to the large difference in enthalpy change seen in this lab however, like the previous reason, this is not a meaningful factor in increasing the enthalpy change. The pressure differences are not extremely different to cause the enthalpy change to increase to as much as they have in this lab. As a result, this is entirely a small contributing factor. Conducting this lab at SATP conditions will eliminate this source of error. In general, the main reason for the larger enthalpy change is due to not be able to tell when the reaction is complete and how the reaction is occurring in the calorimeter.As mentioned earlier, the result in this lab is very rare. This is mainly due to the fact that the Styrofoam calorimeter used to conduct the calorimetric experiment most likely does not provide a perfectly slopped environment. A hole is needed to be made to insert the thermometer. And there were many holes between the lid of the calorimeter and the calorimeter itself. Due to this ineffectiveness of the Styrofoam calorimeter, some of the heat from the reaction would have escaped through the many holes causing a lower final temperature of the reaction and the experimental enthalpy change to be lower than the theoretical (actual) value. As a result, the experimental value is commonly lower than the theoretical (actual) value.Another reason includes the fact that some of the heat released during the reaction would have been transferred to the calorimeter itself instead of transferring to the thermometer. As a result, when the calorimeter and/or field glass of the thermometer absorb the heat, it causes the thermometer to absorb less heat than it should. The final temperature will then be lower than it should be causing a lower enthalpy change. Even though this is not a main reason why the experimental molar enthalpy should be lower than the actual molar enthalpy it still contributes to it. As a result, with the combination of these factors the experimental enthalpy change should be lower than the theoretical value be cause a crapper of heat is able to escape into the calorimeter and into the air due to there being holes in the calorimeter.