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Student Question

Secondary IV • 1yr.

In one of my exercises, we must find out the quantity of product of a photosynthesis reaction such as this one:

CO2 + H2O → C6H12O6 + O2

The initial concentration of Carbon Dioxide is 62 mol / L, and the oxygen's concentration is 84 mol / L.


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Explanations (1)

  • Explanation from Alloprof

    Explanation from Alloprof

    This Explanation was submitted by a member of the Alloprof team.

    Team Alloprof • 1yr.

    Thank you for your question!

    First, the reaction must be balanced, resulting in the following equation:

    6CO2 + 6H2O → C6H12O6 + 6O2

    From this, it is possible to know the concentration of glucose according to a rule of three. But before that, you have to identify the limiting reagent, in other words, the one consumed entirely. In this case, it is carbon dioxide, as it is the molecule with the lowest concentration or quantity in a proportional manner. After that, another rule of three needs to be done:


    62mol / L⇒?

    In this case, divide the initial concentration of carbon dioxide by a factor of 6 giving us a concentration of 20.7 mol / L. If you need the quantity in grams, for example, you would need the volume of CO2 or glucose.

    Finally, there are multiple ways to solve stoichiometric equations. For instance, we can solve them using a table. If you need a more detailed explanation or if you have other questions, don't hesitate!