Answer:
Many plants have thorns on their stems or leaves. What is the MOST likely explanation for the evolution of thorns?
A) Thorns help plants produce more food from photosynthesis.
B) Thorns are an example of a mutation that arises in the genetic code of plants.
C) Thorns help plants to conserve resources like water and soil nutrients that may be used by other organisms.
D) Thorns are an adaptation that some plants have evolved in order to discourage herbivores from eating the plant.
2)
Explanation:
Answer:
To increase the yield of H₂ we would use a low temperature.
For an exothermic reaction such as this, decreasing temperature increases the value of K and the amount of products at equilibrium. Low temperature increases the value of K and the amount of products at equilibrium.
Explanation:
Let´s consider the following reaction:
CO(g) + H₂O(g) ⇌ CO₂(g) + H₂(g)
When a system at equilibrium is disturbed, the response of the system is explained by Le Chatelier's Principle: <em>If a system at equilibrium suffers a perturbation (in temperature, pressure, concentration), the system will shift its equilibrium position to counteract such perturbation</em>.
In this case, we have an exothermic reaction (ΔH° < 0). We can imagine heat as one of the products. If we decrease the temperature, the system will try to raise it favoring the forward reaction to release heat and, at the same time, increasing the yield of H₂. By having more products, the value of the equilibrium constant K increases.
The whitening toothpastes showed differences in their physical-chemical properties. All toothpastes promoted changes to the surface, probably by the use of a bleaching agent.
Explanation:
<em><u>Solutions. 1. If 47 g of KCl dissolved in enough water to give 375 mL of soloution, what is the molarity ... vo volume of solute . ... v/v ethanol, how much 95% v/v ethanol ... prepare 200. mL ...</u></em>
