Use chemical formulas to generate the stoichiometric factor needed to express the results of a gravimetric analysis in terms of the substance on the left if the weighting form is the substance on the right:

Sought Weighted
I Mg Mg2P2O7
II UO2 U3O6

You're looking for what we called in much earlier days the chemical factor. It is taught less and less theses days but is very useful.

2Mg/Mg2P2O7

3UO2/U3O6 (NOTE: I assume U3O6 is a made up part of the problem. I would have written it as UO2 but then there is no conversion fctor needed.)

To generate the stoichiometric factor, we need to use the chemical formulas of the substances involved in the gravimetric analysis. We will use the balanced chemical equations for the reactions involved, and then calculate the stoichiometric factor based on the mole ratios between the substances.

For Sought I, the given weighted form is Mg2P2O7. The balanced chemical equation of the reaction would be:

2 Mg + P2O5 → Mg2P2O7

From this equation, we can see that 2 moles of Mg react with 1 mole of P2O5 to form 1 mole of Mg2P2O7. Therefore, the stoichiometric factor for Sought I is 2.

For Sought II, the given weighted form is U3O6. The balanced chemical equation of the reaction would be:

3 UO2 → U3O6

From this equation, we can see that 3 moles of UO2 react to form 1 mole of U3O6. Therefore, the stoichiometric factor for Sought II is 3.

In summary:
- For Sought I (Mg), the stoichiometric factor is 2.
- For Sought II (U), the stoichiometric factor is 3.