Enthalpy Of Neutralization Lab Report

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Research Question: To compare the enthalpy change of reaction of 3 neutralization reactions by using 3 different acids of distinct pH. The same base of NaOH will be used in all three experiments.

Introduction: Chemical reactions always have energy change. Energy in the form of heat, if liberated is known as exothermic and if absorbed in the reaction is known as endothermic. When a reaction carried out under standard condition at a of temperature 298K and 1 atm of pressure and 1 mole of water is formed it is called the starndard enthalpy of neutralisation (ΔHno). The heat (Q) released during a reaction is calculated by Q = m cp ΔT. The m is the mass of the solution, Cp the specific heat capacity of the solution and ΔT is the temperature change
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The stronger the base the faster the reaction is neutralised.

Controlled Variable How it was controlled Why it was controlled
Molarity of Base The base was made by weighing it out against a weighing scale which was then diluted in distilled water The stronger the base the faster the acid is neutrailsed which in turn affects the rate of the reaction which probably affects the temperature.
Room Temperature The room temperature was regulated with AC kept on through out the experiment The temperature of the room will affect the rate of the reaction affecting the heat released
Volume of Base A measuring cylinder was used to use a specific volume of the base for the reaction. More amount of the base will required more amount of acid to neutralise it which will affect the reaction
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• Subtract the mass of the conical flask from the mass of the neutralised solution to find m. The specific heat capacity of each solution is assumed to be the same as water which is 4.184 JK-1g-1 which is the cp. ΔT which is the temperature change can be found by subtracting the initial temperature of the solution from the final temprature which was found using the data logger.
• The enthalpy change can then be calculated after all these values are found. Each trial can then be avaraged to find a more accurate result for our experiment.

Conclusion and evaluation:

The titration should be carried out carefully while making sure the color of the neutralized solution is the same for all the trials. This can be done by keeping the first sample aside that can be used for reference of the other trials can do this. The readings should be made accurately to avoid having inaccurate results. While titrating the solution should be stirred continuously to make it mix properly with the acid. During the experiment you should make sure none of the solution sticks to the surface of the glass while being transferred, this could affect the reaction and thus the

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