Photosynthesis allows plants to turn light energy into chemical energy by forming glucose from carbon dioxide and water: 6co2(g) + 6h2o(l) → c6h12o6(g) + o2(g) δhrxn = 2802.8 kj the glucose is then used to form complex carbohydrates that the plant needs to survive. a 1.70 lb sweet potato is approximately 73% water by mass. if the remaining mass is made up of carbohydrates derived from glucose (mw = 180.156 g/mol), how much carbon dioxide (mw = 44.01 g/mol) was needed to grow this sweet potato? g how much light energy does it take to grow the 1.70 lb. sweet potato if the efficiency of photosynthesis is 0.86%? kj

305 g of CO₂

3.77 × 10⁵ kJ

Explanation:

Let's consider the global reaction for photosynthesis.

6 CO₂(g) + 6 H₂O(l) → C₆H₁₂O₆(g) + 6 O₂(g)  ΔHrxn = 2802.8 kJ

A 1.70 lb sweet potato is approximately 73% water by mass. If the remaining mass is made up of carbohydrates derived from glucose (MW = 180.156 g/mol), how much carbon dioxide (MW = 44.01 g/mol) was needed to grow this sweet potato?

Let's consider the following relations:

Then, for a 1.70 lb potato:

How much light energy does it take to grow the 1.70 lb. sweet potato if the efficiency of photosynthesis is 0.86%?

According to the enthalpy of the reaction, 2802.8 kJ are required to produce 1 mole of glucose. Then, for a 1.70 lb potato:

a. energy is absorbed in the reaction.

if in a given reaction the energy of products is greater than the energy of reactants it means that reaction is endothermic and during the reaction, the energy is absorbed by reactants. in an endothermic reaction, the products have more stored chemical energy than the reactants. and in this reaction the reactants are more stable than products before the compounds with less energy are always more stable.

substituting a hydrogen atom with a halogen in a hydrocarbon:

- the single bond remains single. a is wrong.

- the bond with hydrogen is as strong as with a halogen. c is wrong

- a hydrocarbon is saturated if there is no double bond. we do not know that so d is wrong.

- carbon will always have four valence electrons. e is wrong.

by elimination, the correct answer is b. the boiling point of the new compound increases.