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Chemical reactions involve energy changes—some release energy (exothermic), while others absorb it (endothermic). The amount of energy transferred depends on the type and amount of reactants. The reaction rate can be increased by adding more reactants, raising the temperature, or improving particle distribution to encourage more collisions.

00:00 Intro
00:26 Endothermic vs Exothermic rxns (recap)
00:51 Controlling the amount of energy transferred
04:21 Controlling the rate of energy transfer
07:06 Summary

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