Question
. Describe an experiment to show how the heat of neutralization of nitric acid by sodium hydroxide can be determined. The description should end with data collection . If 100cm^3 of MHNO_(3) were mixed with 100cm^3 of M KOH at 25^circ C and the temperature rose to 32^circ C Calculate the heat of neutral
Solution
4.5
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Martim
Profissional · Tutor por 6 anos
Resposta
To determine the heat of neutralization of nitric acid (HNO3) by sodium hydroxide (NaOH), you can perform an experiment using a calorimeter. Here's a step-by-step description of the experiment:1. **Setup:** - Obtain a calorimeter, which is an insulated container designed to measure the heat of chemical reactions. - Measure and record the initial temperature of the calorimeter and the solution inside it. In this case, the initial temperature is 25°C.2. **Measurement:** - Measure and record the volume of nitric acid (HNO3) and sodium hydroxide (NaOH) solutions. In this case, both solutions have a volume of 100 cm³. - Pour the measured volumes of HNO3 and NaOH into separate containers.3. **Mixing:** - Slowly mix the HNO3 and NaOH solutions together in the calorimeter. Ensure that the mixing is done gradually to avoid rapid temperature changes that could affect the accuracy of the measurement.4. **Temperature Measurement:** - After mixing, quickly close the calorimeter lid to minimize heat loss to the surroundings. - Measure and record the final temperature of the solution inside the calorimeter after the reaction has completed. In this case, the final temperature is 32°C.5. **Data Collection:** - Calculate the heat absorbed or released during the reaction using the formula:
, where
is the heat absorbed or released,
is the total mass of the solution,
is the specific heat capacity of the solution, and
is the change in temperature. - The total mass of the solution can be assumed to be the sum of the masses of the reactants since the volume of water is negligible compared to the volume of the acid and base. - The specific heat capacity of the solution can be approximated as that of water, which is
. - Calculate the change in temperature (
) as the final temperature minus the initial temperature.6. **Calculation:** - Use the formula
to calculate the heat absorbed or released during the reaction. - Since the reaction involves the neutralization of an acid by a base, the heat of neutralization can be calculated by dividing the heat absorbed or released by the number of moles of water produced. The number of moles of water produced can be calculated from the stoichiometry of the reaction.7. **Heat of Neutralization:** - Calculate the heat of neutralization by dividing the heat absorbed or released by the number of moles of water produced.In this specific example, if 100 cm³ of 1 M HNO3 were mixed with 100 cm³ of 1 M KOH, and the temperature rose to 32°C, you would use the above steps to calculate the heat of neutralization.