The goal of this lab was to determine the enthalpy of formation of salicylic acid. Enthalpy of formation is the change of enthalpy, also known as the change of energy, when one mole of a substance is combusted in its standard state. A mole is a standard unit used to quantify how much of a substance you have. Similar to how a dollar is a unit for money in the United States, a mole is a quantitative unit of a substance in chemistry. This experiment was performed by assembling a bomb in class! First, we used a scale to tare the cup and then we added some benzoic acid to the cup. After the cup was remassed with the scale remembering the final and then the cup was remassed on the balance. Is a process of putting the object back on the scale to
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We had to put the salicylic acid in powder form into a container and crank a lever in order to form a pellet. The container had three parts: one where the salicylic acid was added, a second to collect the pellet, and a third to elevate the container to be level with the lever. Another other part of the apparatus had a lever where small circular metal plate came down to squeeze the solid together. The lever was easily jammed, but needed to be cranked a lot of times and so brute force was needed to reset the position. In order to summarize what making the salicylic acid was like, its like using a nut cracker The salicylic acid was not used first because we needed to know the specific Ccal for the calorimeter. Ccal is the heat capacity of the calorimeter, otherwise known as the “very special container”. Heat capacity is the amount of energy needed to change the system by 1˚degree Celsius. By measuring the change in temperature (∆T), and the change in internal energy of the system (∆U), which is given by the value of the reaction, we can determine the Ccal. This value can be used to calculate the ∆H, the change in enthalpy, for the salicylic acid because we will use the same calorimeter. The change in enthalpy gives the amount of energy given off or taken in. This experiment validates the first law of thermodynamics, which states energy cannot be created or destroyed, but it can be transferred. Using the first law of thermodynamics, we will determine the change of enthalpy of the salicylic acid. Our results can clearly demonstrate the first law of thermodynamics; With a change in enthalpy similar to that of the predicted value, it will indicate the law holding up. The experiment was a lengthy process, but was completed and that’s what
We had to put the salicylic acid in powder form into a container and crank a lever in order to form a pellet. The container had three parts: one where the salicylic acid was added, a second to collect the pellet, and a third to elevate the container to be level with the lever. Another other part of the apparatus had a lever where small circular metal plate came down to squeeze the solid together. The lever was easily jammed, but needed to be cranked a lot of times and so brute force was needed to reset the position. In order to summarize what making the salicylic acid was like, its like using a nut cracker The salicylic acid was not used first because we needed to know the specific Ccal for the calorimeter. Ccal is the heat capacity of the calorimeter, otherwise known as the “very special container”. Heat capacity is the amount of energy needed to change the system by 1˚degree Celsius. By measuring the change in temperature (∆T), and the change in internal energy of the system (∆U), which is given by the value of the reaction, we can determine the Ccal. This value can be used to calculate the ∆H, the change in enthalpy, for the salicylic acid because we will use the same calorimeter. The change in enthalpy gives the amount of energy given off or taken in. This experiment validates the first law of thermodynamics, which states energy cannot be created or destroyed, but it can be transferred. Using the first law of thermodynamics, we will determine the change of enthalpy of the salicylic acid. Our results can clearly demonstrate the first law of thermodynamics; With a change in enthalpy similar to that of the predicted value, it will indicate the law holding up. The experiment was a lengthy process, but was completed and that’s what