Before class of Oct. 20:
- Please watch the 4 videos below (11 min, 12 min, 7 min and 7 min)
- Complete the notes. Keep in mind that these notes are for both these videos and the ones for the next lesson;
- Make a comment/question
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chemistry matters
exploring the pleasure of finding things out
chemistry matters 
During these videos, I learned that The negative specific heat of a substance is equal to the positive specific heat of that same substance. I also learned how to find the specific heat of a substance.
In Hess’s law, why are the components of a reaction split up?
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From these videos I learned how to find the specific heat capacity of a substance through Calorimetry and Hess’s Law. Specific heat is the amount of heat necessary to raise 1 gram of a substance by 1 degree Celsius.
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Calorimetry is the measurement of heat flow – temperature change. To calculate calorimetry, we figure out the specific heat, which is mCAT (A is representing delta in this case b/c I don’t know how to put a triangle on here). So, I saw how enthalpy applies to calorimetry. Hess’s Law says that if a reaction is carried out in a series of steps, the enthalpy change for the overall reaction is equal to the sum of the enthalpy changes for the individual steps. We need to keep in mind that if we reverse a reaction, we need to switch the sign of the enthalpy. Also, we need to ensure that all of the reactants and products are added properly and if anything appears on both sides it cancels.
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In these videos I learned about calorimetry and Hess’s law. I also learned how to add chemical reactions together. We know that the overall empathy change will be equal to the sum of individual empathy changes for a reaction according to Hess’s law. This works because empathy is a state function
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In this video I learned how calorimetry is the measurement of heat flow and reviewed specific heat capacity from last year. From the heat transfer equation, we were able to relate that to our enthalpy reaction from the previous lesson and learned that they are the opposites (-enthalphy = +heat transfer)
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In this lesson, I learned about calorimetry (measurement of heat flow). Using the equation q=mCΔT, I can manipulate the terms algebraically to find the heat transferred, the specific heat, the mass, or the change in temperature. Using the Hess’s law, I can find the total enthalpy change for the overall reaction by calculating the sum of the enthalpy changes for the individual steps.
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I learned about calorimetry in these videos and Hess’s law. I learned that enthalpy will be the same no matter the way you calculate it, hence the Hess’s law. I also learned about the heat capacity, the specific heat and molar heat capacities, as well as how to calculate the change of temperature (which the often the heat flow aka enthalpy)
Question: What if a substance is one degree away from melting point, in which case it will be a change of phase?
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In this video I learned about calorimetry and heat capacity, the specific heat and molar heat capacities. I also learned how to calculate the change of temperature.
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Today we learned about calorimetry and Hess’s law. We learned that Hess’s law works becasue enthalpy is a state function.
Question: In calorimetry, we add the mass of the calorimeter and the water right?
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