Chemistry Titration

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F.6/7 Chemistry Practical: Thermometric Titration
Objective:
(a) To perform a thermometric titration in order to determine the enthalpy change of a reaction; (b) To evaluate enthalpy of neutralization for a strong acid and strong base and for a weak acid and a strong base
Group size: Individual
Introduction
In thermometric titration we make use of the fact that reactions in solution are accompanied by temperature changes. For example, the neutralization reaction of hydrochloric acid and sodium hydroxide is an exothermic reaction.
NaOH(aq) +HCl(aq) NaCl(aq) + H2O Hneut: negative
The purpose of this experiment is to determine the concentration of two acids, hydrochloric acid, HCl, and ethanoic acid, CH3COOH in turn with a standardized solution of sodium hydroxide and record the temperatures of the mixtures during the course of the titration. In each case a plot of temperature against time will enable you to determine the maximum temperature rise, from which you calculate both the concentration of the acid and the enthalpy change of neutralization.
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Theory: Give principle/reason to explain how do you determine the concentration of hydrochloric acid and ethanoic acid by titrating with standardized sodium hydroxide and thermometric measurement is used. The following questions should be useful to you. 1. Define the term 'standard molar enthalpy of neutralization'. 2. Give an ionic equation for neutralization reactions. 3. Define the terms 'strong acid' and 'weak acid'. 4. The enthalpy change of neutralization for a very dilute strong acid reacting with a very dilute strong base is constant at -57.6 kJ mol-1. Why is the value constant? 5. Consider the titration of an acid…...

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