UTF-8Breaking and forming bonds
Breaking and Forming Bonds: It is a common misconception that breaking chemical bonds releases energy and bond making requires energy. The opposite is in fact actually true.
Energy must be absorbed to break chemical bonds.
Energy is released when chemical bonds are formed.
Here, this concept is illustrated, in simple terms, in the simulation below.
You should notice that energy is released when a bond forms between the atoms (the heat energy level rises). Energy is absorbed when a bond between the atoms breaks (the heat energy level decreases). Remember that energy is not created or destroyed in these processes, it just changes form.
Also, note that so far, we have considered bond making and breaking processes separately. When we rationalise the energy absorbed or released by a whole chemical reaction, we must consider the whole process, including each of the bond making and breaking steps. The net amount of energy released (exothermic reaction) or absorbed (endothermic reaction) relies on the sum of all of the individual energy changes involved.
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<font color="#CCC" size="6"><strong>Breaking and Forming Bonds</strong> </font>
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At the beginning of the simulation, four free atoms are shown. These
atoms can react to form a diatomic molecule (e.g. 2O  O<sub>2</sub>).
The scale on the right represents heat energy in the system and the atom
colour is scaled according to kinetic energy <strong>(red = high energy,
white = low energy)</strong>. Note that the heat energy level of the
system is very low at the beginning of the simulation.
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Start the simulation and observe how the level of heat energy changes as
bonds form between the atoms, and as the bonds in the resulting diatomic
molecules break to give free atoms again. (You might have to watch for a
couple of minutes. It’s quite relaxing..... really......)
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The energy level may jump around a little due to rotational motion in
the molecules and the calculation method used here, but you should
clearly see differences due to bond formation and cleavage.
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<strong>Take snapshots of the important changes while running the
simulation.</strong>
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<strong>Q4. How does the amount of energy released during bond formation
compare to the amount of energy absorbed during cleavage of the same bond?</strong>
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trueIt is impossible to know from the information provided.The amount released is greater than the amount absorbed.The amount released is less than the amount absorbed.They are the same.3-3301Lowered Bevelorg.concord.modeler.PageTextBox400.0200.0<html>
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