Temperature Change Lab Report

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The Effect of Temperature Change During the Dilution of a Strong Acid

Introduction
According to the Brønsted-Lowry acid-base theory, an acid is a reactant that loses a hydrogen ion to another reactant. A strong acid is when virtually all the molecules of the acid ionises in water. In this experiment, the strong acid used was hydrochloric acid. This acid is formed when gaseous hydrogen chloride reacts with water according to the equation:

When in solution, the hydronium and chloride ions formed will be partially surrounded by water molecules via ion-dipole bonds, an electrostatic force of attraction that exists between charges in the ions and the partial charges in the water molecules. Water molecules surrounding ions is called hydration. …show more content…

The strong acid used in the experiment was hydrochloric acid. Using different types of acid would mean different ions present in solution. This means that there will be different sized ions, meaning that there will be space for different numbers of water molecule. Only using the hydrochloric acid would allow for consistent hydration, as all the ions would be the same size and would provide the same number of molecules to hydrate them. Another controlled variable was the volume of water used. This allows the same number of water molecules available to hydrate the ions in the acid solution. It also means that there will be the same mass of water available to conduct the heat energy released from …show more content…

However, the increased temperature of the new acid solution was at a greater temperature than the ambient temperature and the temperature of the water. This suggests that some of the results obtained were partially due to the fact that some of the heat energy of the acid was transferred to the water, as well as the hydration of ions present in solution. An improvement would be to create the solutions of desired concentration and allow them to reach thermal equilibrium with the surroundings. This would allow more accurate results and the allow for the assumption that the temperature change observed during the experiment would only be due to hydration of

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