Answer:
Need more information.
Explanation:
I believe you either left out info or explained the question confusingly.
Answer:
c is the answer
step by step explanation is not
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:
waste water from nuclear power plant is
generally very harmful for our environment
and for everyone
hope it will help
Answer:
1. Main sequence stars have different masses. The common characteristic they have is their source of energy. They burn fuel in their core through the process of fusing hydrogen atoms into helium.
2. Supergiants are among the most massive and most luminous stars. Supergiant stars occupy the top region of the Hertzsprung–Russell diagram with absolute visual magnitudes between about −3 and −8. The temperature range of supergiant stars spans from about 3,400 K to over 20,000 K.
3. Supergiants develop when massive main-sequence stars run out of hydrogen in their cores.
4. a supernova occur When the pressure drops low enough in a massive star, gravity suddenly takes over and the star collapses in just seconds. This collapse produces the explosion.
5. when a star has reached the end of its life and explodes in a brilliant burst of light
Explanation:
