Mole, Molecules, and Molarity draft V 0.1

Draft 0.1 of a conversion calculator that converts between moles, molarity, and number of molecules.

This is an idea that has been in my notebook for a while. It is based on the challenge many students have understanding the difference between the number of moles and molecules and how these relate the molarity of solutions.

There are no visual elements associated with this calculator yet.

Status V0.1

  • There are two compoents to the illustration
    • An input area that is hidden by default. This allows the user to switch between different conversion types
    • An output area that describes relationships between these values
  • The top line of the output area contatins a description of the input with an editable text field to change the value.
  • Volume amount or units for the molarity values are are locked at 1 and L respectively
  • The numerical input for large and small numbers is confused. The output is in NN × 10nn format but the input needs to be done in e format (NNenn)
  • There is no error checking on inputs. If the math does not work out with the information entered, the output is returned as NaN or infinity
Next Steps:
  • Add some visual elements to guiding readers/users through the concepts addressed with this calculator
  • Consider allowing user to edit water volume amounts and units. This would help demonstrate that now matter what units are used, the molar value is in moles per Liter
  • Provide some guidance about how numbers need to be input for large and small numbers (i.e. when scientific notation is used)
  • Illustration is not scaling with page resize. Need to implement the pymJS dynamic resizing code.
  • The styling of the number entry area needs help. Work on proper rounding, input format/guidance (see above), and text box entry look and feel.
I like having the number entry be in line with the output, but when working with an input type that could have such a large range of possible inputs, it is difficult to settle on an simple, intuitive structure that is robust enough to handle regular numbers, scientific notation, and a range of lengths. The length range issue stems from the possibility that a user may want to enter an arbitrarily long string of number even if from the perspective of significant digits a shorter string would be as or more appropriate.

Watch this space Next >