Consider the halogenation of ethene is as follows:
CH₂=CH₂(g) + X₂(g) → H₂CX-CH₂X(g)
We can expect that this reaction occurring by breaking of a C=C bond and forming of two C-X bonds.
When bond break it is endothermic and when bond is formed it is exothermic.
So we can calculate the overall enthalpy change as a sum of the required bonds in the products:
Part a)
C=C break = +611 kJ
2 C-F formed = (2 * - 552) = -1104 kJ
Δ H = + 611 - 1104 = - 493 kJ
2C-Cl formed = (2 * -339) = - 678 kJ
ΔH = + 611 - 678 = -67 kJ
2 C-Br formed = (2 * -280) = -560 kJ
ΔH = + 611 - 560 = + 51 kJ
2 C-I Formed = (2 * -209) = -418 kJ
ΔH = + 611 - 418 = + 193 kJ
Part b)
As we can see that the highest exothermic bond formed is C-F bond so from bond energies we can found that addition of fluoride is the most exothermic reaction
Answer:
the stem, but if its more specific xylem cells
The path of energy flow from the sun to the humpback whale is as follows:
- Sun---> Plankton ---> Small fishes ---> Humpback whale.
<h3>What is energy?</h3>
Energy is the ability to do work.
The primary source of energy on the earth is the sun.
The energy from the sun is used by producers to produce food on which other organisms depend on.
The energy from the sun gets to the humpback whale through producers such as plankton.
The path of energy flow from the sun to the humpback whale is as follows:
- Sun---> Plankton ---> Small fishes ---> Humpback whale.
Learn more about energy flow at: brainly.com/question/21786633
