Question regarding Calorimetry?

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In summary, a 75 g copper sample is heated to 312 degrees Celsius and then dropped into a glass beaker containing 220 g of water. The beaker has an effective heat capacity of 190 J/K and the initial temperature of the water and beaker is 12 degrees Celsius. To find the common final temperature of the copper, glass, and water, we can use the equations Q = mcΔT and (mw)(cw)(ΔTw) = (mc)(cc)(ΔTc), where Q is the amount of heat, m is the mass, c is the heat capacity, and ΔT is the change in temperature. By converting the heat capacities per gram to heat capacities for the objects and
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Ishida52134
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Homework Statement


A copper sample whose mass mc is 75 g is heated in a laboratory oven to a temperature of 312 degrees Celsius. The copper is then dropped into a glass beaker containing mass mw = 220 g of water. The effective heat capacity of the beaker is 190 J/K. The initial temperature of the water and beaker is 12 degrees Centigrade. What's the common final temperature of the copper, glass, and water?


Homework Equations


Q = mcΔT
(mw)(cw)(ΔTw) = (mc)(cc)(ΔTc)



The Attempt at a Solution


I tried substituting the given values into the equation but I was confused about what to do with the heat capacity of the beaker.
 
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Ishida52134 said:
I tried substituting the given values into the equation but I was confused about what to do with the heat capacity of the beaker.

They don't give you the heat capacity per gram of the beaker or its mass, instead they give you the heat capacity itself. That is, the heat capacity of the beaker as a whole, as if you had a "cb" and "mb" and multiplied them: Cb = cb*mb.

Here's a shortcut you can use when there are no phase changes involved (in this case it's a bit dubious because they don't tell you whether or not any steam generated at first contact of the 312C copper with the water will be contained inside the beaker), Nevertheless...

Convert all the heat-capacities-per-gram to heat capacities for the objects or substances (multiply the given J/kg/K values for the objects by the mass of those objects). Sum them up to find a grand total heat capacity of the system. Next, find the total amount of heat in the system to begin with. That is, sum the heats (Joules) in the individual objects or substances. When steady state is reached the heat will be spread evenly though the whole system. So the total heat and total heat capacity can be used to find the uniform temperature.
 

1. What is calorimetry?

Calorimetry is the scientific measurement of heat transfer between a system and its surroundings. It involves using a calorimeter, which is a device that helps measure the heat exchanged during a physical or chemical process.

2. What is the purpose of calorimetry?

The purpose of calorimetry is to measure the heat released or absorbed during a chemical or physical process. This information can then be used to calculate the specific heat capacity, enthalpy, and other thermodynamic properties of a substance.

3. What are the different types of calorimetry?

The two main types of calorimetry are constant-pressure calorimetry and constant-volume calorimetry. Constant-pressure calorimetry measures heat transfer at a constant pressure, while constant-volume calorimetry measures heat transfer at a constant volume.

4. How is calorimetry used in scientific research?

Calorimetry is used in scientific research to study the heat changes that occur during physical and chemical processes. It is especially useful in studying reactions that produce or absorb heat, such as combustion reactions or phase changes.

5. What are some applications of calorimetry in everyday life?

Calorimetry has many practical applications in everyday life. It is used in the food industry to determine the nutritional value of foods and in the pharmaceutical industry to measure the energy released during drug reactions. It is also used in the design and testing of insulation materials for buildings and in the development of more efficient engines and fuel sources.

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