Answer:
Carbon dioxide is moving out of the living things.
Explanation:
The food materials eaten by living things contain carbon in the form of complex organic matter. When living things feed, they ingest this complex organic material into their bodies.
During the process of digestion, this complex organic material is broken down to give glucose. Glucose is the energy molecule in living things. Excess glucose in the body is stored as glycogen.
During cellular respiration, glucose is broken down to release carbon dioxide. Hence, at night when the giraffe has stopped eating, cellular respiration continues to occur and carbon dioxide is released, that is, carbon dioxide continues to move out of living things at night.
Question requires a change resulting in an increase in both forward and reverse reactions. Now lets discuss options one by one and see there impact on rate of reactions.
1) <span>A decrease in the concentration of the reactants:
When concentration of reactant is decreased it will shift the equilibrium in Backward direction, so resulting in increasing the backward reaction and decreasing the forward direction. Hence, this option is incorrect.
2) </span><span>A decrease in the surface area of the products:
Greater the surface Area greater is the chances of collision and greater will be the rate of reaction. As the surface area of products is decreased it will not favor the backward reaction. Hence again this statement is incorrect according to given statement.
3) </span><span>An increase in the temperature of the system:
An increase in temperature will shift the reaction in endothermic side. Hence, if the reaction is endothermic, an increase in temperature will increase the rate of forward direction or if the reaction is exothermic it will increase the rate of reverse direction. Hence, this option is correct according to given statement.
4) </span><span>An increase in the activation energy of the forward reaction:
An increase in Activation energy will decrease the rate of reaction, either it is forward or reverse. So this is incorrect.
Result:
Hence, the correct answer is,"</span>An increase in the temperature of the system".
If a metal is less reactive than carbon, it can be extracted from its oxide by heating with carbon. The carbon displaces the metal from the compound, and removes the oxygen from the oxide. This leaves the metal.