Beyond Labz

Overview

The stockroom and unknown tabs are used to select a calorimeter and reagents for work in the laboratory, create practice unknowns, or retrieve assigned unknowns from the instructor. The essential features of the stockroom and unknowns tab are described in the following list. 

• Reagents.  Reagents for calorimetry experiments are selected by clicking on the selected category from the samples menu. One organic reagent can be selected for combustion experiments, one salt can be selected for dissolution experiments, and a reaction pair can be selected for heat of reaction experiments.
• Metals.  Clicking on the metals category expands the category where a pure elemental metal or an alloy sample can be selected for heat capacity measurements. A sample is selected by clicking on the sample. The sample will show up on the stockroom counter in the laboratory. 
• Calorimeters.  The calorimeter section contains the bomb calorimeter, a dewar, and a coffee cup. The bomb calorimeter is used for combustion experiments, and the dewar and coffee cup are used for the remaining experiments. The dewar and coffee cups operate identically, but the dewar has superior insulating qualities compared to the coffee cup. A calorimeter is selected by clicking the calorimeter. It will be placed on the stockroom counter. Only one calorimeter is allowed out in the laboratory at a time.
• Unknown Tab.  The unknown tab is used to retrieve assigned and practice unknowns and to create practice unknowns. Clicking on the "Unknowns" tab will show the window in the image below and allow practice unknowns to be defined.
• Presets.  Clicking on the presets tab gives access to preset thermodynamic experiments that are already predefined and ready to run. This tab also includes user-saved presets. 

Selecting Calorimeters and Reagents

Calorimeters and reagents for the different calorimetry experiments are selected by clicking on the chosen calorimeter or bottles from the stockroom tab and then dragging them from the stockroom counter to the lab bench. This can also be done by double-clicking on the item while it sits on the stockroom counter. One organic reagent can be selected for combustion experiments, one salt can be selected for dissolution experiments, and a reaction pair can be selected for heat of reaction experiments. Only one calorimeter can be out in the laboratory at a time.

Metals 

Clicking on the metals section under samples brings the user to expanded view where a pure elemental metal or an alloy sample can be selected for heat capacity measurements. A sample is selected by clicking on it in the stockroom tab window. The metal sample can then be dragged from the stockroom counter to the lab bench.

Preset Experiments

The presets tab gives access to a list of calorimetry experiments that are predefined and ready to run. To select one of these experiments, click on the presets tab and then click on the desired experiment. The appropriate calorimeter and reagents will be automatically selected and placed on the stockroom counter or laboratory bench. 

The following point should be kept in mind: The preset experiments that are included with the labs cover many of the fundamental calorimetry experiments that demonstrate thermodynamic concepts. These preset experiments are only a small set of the large number of experiments that can be designed and implemented in this simulation.

Creating Practice Unknowns

Practice unknowns can be generated that will allow students to practice experimental procedures and calculations for determining the heats of reaction, solution, or combustion or the heat capacity of a metal without a score being assigned to the result. The practice unknown view is accessed by clicking on the "Unknowns" tab. The key elements of the unknown view include (a) the selector button for the unknown type and (b) the Create Unknown button.

A practice unknown is defined by selecting the type of unknown needed. This is done by clicking on the button of the desired type of unknown and then clicking Create Unknown. This will then place an appropriate unknown reagent, metal, or pair of reagents in the case of a reaction unknown on the stockroom counter. A heat of reaction, solution, or combustion or a heat capacity for the metal will be randomly assigned to the unknown and can be revealed by clicking the Reveal button. It can be hidden again by clicking the Hide button that replaces Reveal. An unknown can be removed by clicking the trash icon next to the Reveal button.