Download presentation
Presentation is loading. Please wait.
Published byDana Harris Modified over 9 years ago
1
+ Chemical Energy
2
+ Hmmm… Can you list 5 energy sources that do not directly produce carbon dioxide?
3
+ Cellular Respiration C6H12O6 + 6O2 6CO2 + 6H2O What type of reaction does this look like? Where would energy go in this reaction?
4
+ Fossil Fuels Why can fossil fuels be considered as a stored solar energy source?
5
+ Types of Energy Kinetic Energy = energy of motion Thermal Energy = heat = movement of particles Potential Energy = stored
6
+ Heat Heat = thermal = kinetic energy (using the definitions from the previous slide, explain to your partner how this could be)
7
+ q = mc Δ t (heat formula) q = heat, kinetic energy (J or kJ) m = mass c = specific heat capacity – amount of energy involved in changing the temperature of 1g of a substance by 1 o C Δ t = change in temperature
8
+ Think About THIS! If you are heating water and metal at the same temperature, which one will heat up faster? Why? How do we relate that to Heat Capacity?!
9
+ EXOTHERMIC CHANGE System loses energy
10
+ ENDOTHERMIC CHANGE System gains energy
11
+ Example: Calculate the energy released when 250mL of water cools down from 98.0C to 25.0C. (c for water = 4.19J/g/C)
12
+ Example 2: Calculate the heat capacity of a pot that water is heated in when the energy required to heat the 300gram pot from 12C to 112C is 11.7kJ.
13
+ Remember: Endothermic reactions energy is ABSORBED (surroundings get cooler) Exothermic reaction energy is RELEASED (surroundings get warmer)
14
+ Enthalpy Enthalpy involves only changes in POTENTIAL ENERGY changes in bond energy
15
+ 3 types of enthalpy changes (Ep) phase change – intermolecular bonds (forces) chemical change – intramolecular bonds (ionic / covalent) nuclear change – protons and neutrons are altered
16
+ For tomorrow… How can we relate HEAT or Thermal energy to ENTHALPY????
Similar presentations
© 2024 SlidePlayer.com Inc.
All rights reserved.