Identify the necessary parts to build a calorimeter. Select one or more:
a. Cover
b. Thermometer
c. Conductivity probe
d. An exterior paper cup
e. An interior paper cup
f. An interior Styrofoam cup
g. An exterior Styrofoam cup
The Correct Answer and Explanation is:
Correct answers: a. Cover, b. Thermometer, f. An interior Styrofoam cup, g. An exterior Styrofoam cu
A calorimeter is a device used to measure the heat transfer during physical or chemical changes, particularly in reactions. The simplest form of a calorimeter, often used in high school or introductory college labs, is a coffee cup calorimeter, which is typically constructed using Styrofoam cups and basic lab tools.
- Cover (a): A cover is essential to minimize heat exchange between the calorimeter’s contents and the external environment. It helps trap heat inside the system, improving accuracy by reducing energy loss to the surroundings.
- Thermometer (b): This is crucial for measuring the temperature change of the substance or solution inside the calorimeter. The observed change in temperature is used to calculate the heat transfer using the formula q=mcΔTq = mc\Delta T, where mm is mass, cc is specific heat capacity, and ΔT\Delta T is the temperature change.
- Interior Styrofoam cup (f) and Exterior Styrofoam cup (g): Styrofoam is an excellent thermal insulator, which is why it’s preferred over paper for calorimetry. The interior cup holds the reaction mixture or solution. The exterior cup adds structural support and further insulates the system, reducing heat exchange with the environment.
The other options, while potentially useful in other experiments, are not necessary for a standard calorimeter:
- Conductivity probe (c): Measures electrical conductivity, not relevant in calorimetry.
- Exterior or interior paper cup (d, e): Paper is less effective at insulating compared to Styrofoam and is more prone to heat loss, making it a poor choice for accurate calorimetric measurements.
Thus, the correct configuration for an efficient and functional calorimeter includes a cover, thermometer, and a double-layered Styrofoam cup setup.
