Halogens I'm pretty sure. The next to last group on the right of the periodic table.
Opposite charges on positive and negative ions attract each other.
Answer:
That periodic trends are specific patterns that are present in the periodic table that illustrate different aspects of a certain element, including its size and its electronic properties.
Explanation:
Answer:
The question lacks options, the options are:
A) Energy is transferred to consumers, which convert it to nitrogen and use it to make amino acid
B) Energy from producers is converted into oxygen and transformed to consumers.
C) Energy from the sun is stored by green plants and transferred to consumers.
D) Energy is transferred to consumers, which use it to produce food.
The answer is C
Explanation:
Organisms obtain energy in an ecosystem by feeding on one another in a chain called FOOD CHAIN. Energy is transferred when one organism feeds on another. A food chain always begins with a PRODUCER, which is an autotrophic organism capable of producing its own food via light energy from the sun.
In a terrestrial ecosystem, the energy a plant captures via Its Chlorophyll is used to produce food during photosynthesis. This energy is stored in the plants and transferred when a set of organisms called PRIMARY CONSUMER feeds on the plant. The transfer continues in that order till decomposers.
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
