Endothermic

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Endothermic Exothermic Change
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Whenever chemical reactions occur, energy is
transferred to or from the surroundings.
An exothermic reaction is one which transfers
heat energy to the surroundings
An endothermic reaction is one which takes heat
energy from the surroundings
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Exothermic process a physical or chemical change
that releases heat energy
Exothermic Change - heat is given off and the
temperature rises
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Reactants ? Products Energy as Heat
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Exothermic Examples

• Chemical Change
• A candle flame
• Rusting iron
• Burning sugar
• Glow sticks
• Fire crackers
• Physical Change
• Some hand warmers
• Some dissolving

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Endothermic process a physical or chemical
change that requires (or absorbs) heat energy
Endothermic reaction - heat is taken in and the
temperature may drop
Photosynthesis is an endothermic reaction
(requires energy input from sun)
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Reactants Energy as Heat ? Products
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Endothermic Examples

• Chemical Change
• Baking bread
• Cooking an egg
• Physical Change
• Sometimes dissolving
• Cold packs from nurse