Question

When glucose is consumed, it reacts with oxygen in the body to produce carbon dioxide, water, and energy. How many grams of carbon dioxide would be produced if45 g of `C_6H_12O_6` completely reacted with oxygen?

Answer 1

66 grams `CO_2`

Explanation:

First, find the balanced chemical formula:

`C_6H_12O_6 + 6O_2 rarr 6CO_2 + 6H_2O`

Since glucose forms carbon dioxide in a 1:6 ratio, we know that one mole of glucose yields 6 moles of carbon dioxide. So in order to find the moles of carbon dioxide formed, we need to multiply the moles of glucose by 6.

`"moles " C_6H_12O_6 = (45g) / "molar mass of glucose"`

`"moles " C_6H_12O_6 = (45g) / (180.15588 g/(mol))`

`"moles "C_6H_12O_6 = 0.249783687 mols`

`"moles "CO_2 = 0.249783687mols * 6`

`"moles "CO_2 = 1.498702124mols`

To find grams of carbon dioxide, just multiply the moles of `CO_2` by `CO_2`'s molar mass.

`"grams " CO_2 = 1.498702124mols * 44.0095 g/(mol)`

`"grams " CO_2 = 65.957131124 grams`

Since you only have 2 sig figs, the answer would be 66 grams.