# Question a0bc7

Nov 28, 2015

$\text{0.001 moles}$

#### Explanation:

As you know, plants use the photosynthesis reaction to convert carbon dioxide and water, in the presence of light and chlorophyll, into glucose and oxygen gas.

The key to this problem is the balanced chemical equation for the photosynthesis reaction, which looks like this

$6 {\text{CO"_text(2(g]) + 6"H"_2"O"_text((l]) + color(blue)("light") -> "C"_6"H"_12"O"_text(6(s]) + 6"O}}_{\textrm{2 \left(g\right]}}$

Notice that you have a $1 : 1$ mole ratio between carbon dioxide and oxygen gas.

More specifically, for every $6$ moles of carbon dioxide required by the reaction, $6$ moles of oxygen gas are produced.

In your case, you want the chamber to maintain an initial number of $0.003$ moles of ${\text{CO}}_{2}$. If the reaction produces $0.001$ moles of ${\text{O}}_{2}$ per hour, it follows that it consumes, per hour

0.001 color(red)(cancel(color(black)("moles O"_2))) * "6 moles CO"_2/(6color(red)(cancel(color(black)("moles O"_2)))) = "0.001 moles CO"_2#

This means that the number of moles of carbon dioxide will decrease by $0.001$ per hour. In order to keep it constant, you will need to add $0.001$ moles of carbon dioxide per hour.