Question

the chemical formula for glucose, a simple sugar, is c6h12o6. when a glucose molecule is assembled during photosynthesis, the process takes up 12 hydrogen ions from the stroma of the chloroplast.

what process adds 12 hydrogen ions to the chloroplast?
standard addressed:

other sugar molecules reacting with oxygen in the chloroplast
12 water molecules splitting apart during the light-independent reactions
6 water molecules splitting apart during the light-dependent reactions
12 water molecules splitting apart during the light-dependent reactions

Explanation:

Identify the source of hydrogen ions

Using the Photosynthesis Reactions knowledge point

$$ 2\text{H}_2\text{O} ightarrow 4\text{H}^+ + 4e^- + \text{O}_2 $$

Calculate the required water molecules

Using the Light-Dependent Reactions knowledge point

$$
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$$

Determine the correct reaction phase

The splitting of water molecules (photolysis) occurs during the light-dependent reactions in the thylakoid membrane, releasing oxygen, electrons, and hydrogen ions (protons). Therefore, 6 water molecules must split during the light-dependent reactions to yield 12 hydrogen ions.

Answer:

• other sugar molecules reacting with oxygen in the chloroplast
• 12 water molecules splitting apart during the light-independent reactions
• 6 water molecules splitting apart during the light-dependent reactions (Correct answer)
• 12 water molecules splitting apart during the light-dependent reactions