All of the experiments used in the simulation have LCD (Liquid Crystal Display) controllers that are used to read and control the variables in each experiment. The LCD controllers can be read from the wide or zoomed in view but can only be changed from the Live Data tab. The LCD controllers used in the experiments can be divided into four types: (1) Dependent Variable Controllers, (2) Independent Variable Controllers, (3) Dual Purpose Controllers, and (4) Ideal Gas Mixture Controllers.
Dependent Variable Controllers. In each experiment, there are one or more variables that are dependent on the values of the independent variables. The LCD controllers for these variables are often the top LCD controllers of the experiment. The values of these controllers cannot be changed except by changing the other variables. The units of the dependent variables can be changed by clicking on the Units button in the lower right-hand corner. The displays for these controllers have a gray background.
Independent Variable Controllers. These LCD controllers are used to change the values of the independent variables. The value of any independent variable can be changed by either (1) clicking on the arrows above or below the desired digit to change or (2) clicking on the digit to be changed and typing in a new number. When a digit is selected by clicking on it, a curser will show up in the box to indicate where the typed digits will go. An additional feature is the rounding button located in the upper left-hand corner of the LCD controller. Each time the rounding button is clicked, the value on the LCD controller is rounded to the next highest significant figure. It can be clicked multiple times to continue rounding to the most significant digit.
Dual Purpose Controllers. The only LCD controller of this type is used in the cylinder experiment to display both the number of moles and the volume of gas trapped by the piston in the cylinder. The volume is a dependent variable in this experiment and cannot be changed. The number of moles in the experiment can only be changed before the piston is placed on the cylinder by changing the temperature and/or pressure in the chamber. The two different variables can be alternately displayed by clicking on the switch in between the "Volume" and "Moles" labels on the LCD controller. Clicking on the Units button will change the units used for the volume display. Both volume and moles are displayed in the Live Data tab of the laboratory.
Ideal Gas Mixture Controllers. These LCD controllers only exist for the pressure and number of moles when there is an ideal gas mixture. These mixture controllers have a table that displays up to eight different gases below all other controllers as well as a P Total and n Total controller - often at the top. The table only displays gases that have been added to the experiment. Notice that the table displays the partial pressure (in kPa) and moles of each gas added to the experiment. The P Total controller will display the total pressure and the n Total controller will display the total number of moles for the gas mixture.