In photosynthesis, 6 molecules of carbon dioxide combine with an equal number of water molecules through a complex series of reactions to give a molecule of glucose having a molecular formula C₆ H₁₂ O₆. How many grams of water would be required to produce 18 g of glucose? Compute the volume of water so consumed assuming the density of water to be 1 g cm^–3.

During photosynthesis, following reaction takes place:

6 CO₂ + 6H₂O → C₆H₁₂O₆ + 6O₂

1 mole glucose needs 6 moles of water.

Molar mass of glucose (C₆ H₁₂ O₆) = 180g

molar mass of water = 18g

We know, Number of moles =

180 g of glucose needs = (6 x 18)g of water

1g glucose will need =

18g glucose would need =

Volume =

The density of water = 1 gcm^-3

Therefore, volume of water consumed = =