Scaling API-first – The story of a global engineering organization
Exothermic and endothermic
1.
2. How did fossil fuels form?
500 million years ago living matter-
mostly plants- died and was buried in
sediment.
Pressure, heat, and microbes converted
the organic matter into petroleum.
Buried sunshine?
6. Chemical energy
A form of potential energy that is stored
in the bonds of chemical compounds.
Burning hydrocarbons releases energy
in the form of heat and light
7. Types of energy in chemical
reactions
Endothermic: energy “enters” the
reaction
Feels ________________
Exothermic: energy “exits” the reaction
Feels ________________
8. Reactions take place in 2 steps:
1) Bonds must be broken in the starting
reactants.
* When bonds are broken, energy is
released. So this is an exothermic
process.
CH4 + 2O2 C + 4H + 4O + Energy
9. Step 2:
Separated atoms now join to form a new
bonds to make the products.
It takes energy to form bonds, so this
process is endothermic.
Energy + C + 4H + 4O CO2 + 2 H2O
11. Net equation for burning of
methane
CH4 + 2O2 CO2 + 2H2O + energy
Notice the energy shows up as a
product so more energy was released
so the reaction is exothermic.
gummy bear experiment
12. Energy + 2H2O 2H2 + O2
Is more energy put into the reaction or
released by the reaction?
Is the reaction endothermic or
exothermic?
endothermic reaction