Personal Tutor Setup Help

Let's suppose that the student is not at the point of knowing how to get started on a problem. The Personal Tutor can help by showing the student how this problem can be setup step-by step. As this demonstration proceeds, the Personal Tutor can provide additional checks to that would promote additional understanding.

Personal Tutor Help:

1. The Personal Tutor provides ShowMe help: Shows the student, step-by-step, how to set up the solution to the problem. However, some additional help (2-7) is available that may answer some of the student's questions during this process.

2. The Personal Tutor provides Hints: The student might take advantage of these hints to complete the setup on their own.

3. The Personal Tutor will check the units expected in answer.

4. The Personal Tutor can help the student's visual understanding of how the factor-label method tracks units when supported by Color Tiles.)

5. The Personal Tutor can show the student how to cancel units.

6. The Personal Tutor allows the student to Invert ratios in the setup.

7. The Personal Tutor includes a Conversion Factor generator that can provide key information needed to complete the setup:
   • Unit conversion factors are generated from unit labels.

   • Formula weight (molar mass) is calculated from a written chemical formula.

A. Setting up the solution to a density calculation problem (Qktour problem 2.3)

To get started, the student might open up the Hints list box. This one hint may be sufficient for the student to get started on the setup. If not, the student can ask the Personal Tutor to get them started by clicking on the ShowMe button. However, the first ShowMe message provides this same information as well.

The second ShowMe message offers to insert the first term of the setup.

The student canl accept this offer by clicking on the Yes button, which will insert the volume of aluminum. The density of aluminum will be inserted if the second ShowMe offer is accepted. In this figure, the student has clicked on the Units button to check the units expected in the answer from this setup.

Turn on the Color Tiles to see why this setup would give the predicted units in the answer (once the identical units are cancelled).

(Clicking on the divisor bar separating the numerator and denominator, followed by a unit check reveals why the units would not cancel in this setup.)

After the student cancel units, a unit check shows only one unit remains. (Additional requests for help from Personal Tutor are limited to the suggestion that the student use the pop-up calculator to complete the arithmetic.)

Locating Data

If the student was setting up this problem in a "blank" Problem Solving WorkPad, the density of aluminum may be "dragged and dropped" from the Element Mode into the setup. (I contemplate including other data tables in future versions of the chemical calculator that will be needed for particular problems.)

B. Setting up the Solution to a mole conversion problem (Qktour problem 3.31)

The setup for this problem may require some additional information: the molar mass of calcium hydroxide. The molar mass of calcium hydroxide is available in the Hints list box. (You can also calculate the molar mass directly from the chemical formula. See the discussion below.)

The setup for this problem is similar to that created for density calculation problem, except that non-unit labels must be included as part of the complete setup and correct answer. (This figure also includes the results of a unit check.)

The identities of the unit- and non-unit labels are more easily distinguished when the Color Tiles are turned on.

C. Generating Conversion Factors

1. Molar Mass

The molar mass can be generated directly from a "written" chemical formula. In this illustration, I have written the chemical formula of calcium hydroxide (for which I want to find its molar mass) in the numerator (for a setup not requiring a non-unit label). The molar mass is generated when you click on the Factors button.

Let us repeat this in the Problem Solving WorkPad, which includes space for the non-unit labels. (It is not necessary, however, to include the non-unit label.) Click on the Factors button to generate the molar mass.

2. Unit Conversion Factors

We can generate a unit conversion factor from the unit labels. Click on the Factors button to generate the conversion factor.