UTF-8Chemical Reactions: Activation Energy227223152
Reaction Rates, Catalysis, and Energy: Activation energy.
If activation energy is low - the chemical reaction will happen easily or even without the input of any additional energy (e.g. when you mix baking soda and vinegar)
If activation energy is high - a huge input of energy may be needed to get the reaction to happen (e.g. when you bake food in the oven)
Instead of two atoms forming a single molecule (combination), we will now experiment with how two molecules can react to form a third kind of molecule (double displacement). The reaction will be A2 + B2 --> 2 AB.
EXPERIMENTING WITH THE MODEL
1. Adjust the A2 and/or B2 bond strength.
2. Run the model.
3. Add heat by repeatedly pressing the "heat" button until the reaction occurs.
4. Reset the model, and repeat the above steps, but change the bond strengths to some different values. Initially, it is recommended to only change one bond strength at a time between pressing reset.
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<font size="4" face="Verdana, Arial, Helvetica, sans-serif">If you mix a
bunch of hydrogen (H<sub>2</sub>) and oxygen (O<sub>2</sub>), nothing will
happen ... unless there is a spark or flame, which would cause a huge
explosion.<br><br>Inside every (non-electric) car engine, spark plugs do
just that: they provide a spark of energy to get the gasoline to burn at
just the right moment to make the engine work properly.<br><br>The energy
it takes to make a reaction happen is the <strong>activation energy</strong>
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<font size="4" face="Times,serif"><strong>Why do you need to make sure the substances (A<sub>2</sub> and B<sub>2</sub>) have enough heat energy before they will react? Why don't they just form AB at any temperature?</strong></font>
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<font size="4" face="Times,serif"><strong>Activation energy is the energy
needed to get a reaction started. Usually, this is the heat energy of the
reactants. If something has a high activation energy, then it is hard to
get the reaction to happen unless the temperature is high, or there is
another significant source of energy. If the bond between A-A or B-B is
very strong, then the activation energy for the reaction will be:</strong></font>
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highlowthe bond strength will not affect the activation energy0 Line11org.concord.modeler.PageTextArea650<html>
<font size="4" face="Times,serif"><strong>Some reactions in your body happen very slowly at body temperature and some happen more quickly. Why might this be true? (Be sure to discuss bond strength and activation energy in your answer.)</strong></font>
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