| Ratio Method |
Recipe Method |
| Method has no direct analogy to anything in
a student's life experience. |
Method is analogous to the concept of a
recipe which can be scaled up or down depending on need and/or availability of materials. |
| Finds how much of a single unknown
will be involved in a reaction when given a single component. Looks at only two
components in an equation. |
Looks at one component, finds a multiplier
which can be used globally and applied to the whole equation. |
| Ratio may change as each component is
determined. |
Multiplier stays constant. |
| For 2 reactant/2 product system 12 possible
ratios. |
Only one multiplier. |
| Use Factor label method throughout with
labels canceling. |
Students determine a dimensionless
Multiplier. |
| Calculations easily chained
together.Limiting reactant problems involve using 2 sets of mole ratios to determine which
reactant will produce least mole of desired product. |
Calculations done stepwise. Reduced
chainability. |
| In limiting reactant problems, use mole ratios
to find the amount of one in relation to the other. |
In limiting reactant problems, solve for
two multipliers, whichever one is the smallest is limiting. |
| Traditional
method taught universally, no need to learn new method for students pursuing further
chemistry courses. |
Non-traditional method, more applicable to
non-science majors. Students in later course - AP Chem - have no problem learning
traditional method. However, 1/2 of those taught traditionally, when shown this method,
have adopted it with less than 1/2 hr of explanation. |
| Confusion
or lack of success with this method may discourage students from pursuing further chem
study. |
Success with this method may encourage
students to pursue further courses in chemistry. |
| |
Has another use of the variable letter M |
