Your SlideShare is downloading. ×
0
C7 energy levels
C7 energy levels
C7 energy levels
C7 energy levels
C7 energy levels
C7 energy levels
C7 energy levels
C7 energy levels
C7 energy levels
C7 energy levels
C7 energy levels
C7 energy levels
C7 energy levels
C7 energy levels
C7 energy levels
C7 energy levels
C7 energy levels
C7 energy levels
C7 energy levels
C7 energy levels
C7 energy levels
C7 energy levels
C7 energy levels
C7 energy levels
C7 energy levels
C7 energy levels
C7 energy levels
C7 energy levels
C7 energy levels
C7 energy levels
C7 energy levels
C7 energy levels
Upcoming SlideShare
Loading in...5
×

Thanks for flagging this SlideShare!

Oops! An error has occurred.

×
Saving this for later? Get the SlideShare app to save on your phone or tablet. Read anywhere, anytime – even offline.
Text the download link to your phone
Standard text messaging rates apply

C7 energy levels

1,628

Published on

Published in: Technology, Business
0 Comments
0 Likes
Statistics
Notes
  • Be the first to comment

  • Be the first to like this

No Downloads
Views
Total Views
1,628
On Slideshare
0
From Embeds
0
Number of Embeds
1
Actions
Shares
0
Downloads
11
Comments
0
Likes
0
Embeds 0
No embeds

Report content
Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

Cancel
No notes for slide

Transcript

  • 1. Energy Levels
  • 2. Energy Levels Exothermic reactions <ul><li>Energy is given out </li></ul><ul><li>The products have less energy than the reactants </li></ul>Combustion and neutralisation are exothermic
  • 3. Energy Level Diagrams Exothermic reactions energy
  • 4. Energy Level Diagrams Exothermic reactions energy course of reaction
  • 5. Energy Level Diagrams Exothermic reactions energy course of reaction reactants
  • 6. Energy Level Diagrams Exothermic reactions energy course of reaction reactants products
  • 7. Energy Level Diagrams Exothermic reactions energy course of reaction reactants products energy given out ∆ H is negative
  • 8. Energy Level Diagrams Endothermic reactions <ul><li>Energy is taken in </li></ul><ul><li>The products have more energy than the reactants </li></ul>The energy is taken in from the surroundings
  • 9. Energy Level Diagrams Endothermic reactions energy
  • 10. Energy Level Diagrams Endothermic reactions energy course of reaction
  • 11. Energy Level Diagrams Endothermic reactions energy course of reaction reactants
  • 12. Energy Level Diagrams Endothermic reactions energy course of reaction reactants products
  • 13. Energy Level Diagrams Endothermic reactions energy course of reaction energy taken in ∆ H is positive reactants products
  • 14. Summary Table Exothermic reactions Endothermic reactions
  • 15. Summary Table Exothermic reactions Endothermic reactions Energy is given out to the surroundings Energy is taken in from the surroundings
  • 16. Summary Table Exothermic reactions Endothermic reactions Energy is given out to the surroundings Energy is taken in from the surroundings ∆ H is negative ∆ H is positive
  • 17. Summary Table Exothermic reactions Endothermic reactions Energy is given out to the surroundings Energy is taken in from the surroundings ∆ H is negative ∆ H is positive Products have less energy than reactants Products have more energy than reactants
  • 18. ∆ H How much energy is given out or taken in? <ul><li>Energy is needed to break chemical bonds </li></ul><ul><li>Energy is given out when bonds are made </li></ul>∆ H is the difference between the energy needed to break the bonds in the reactants, and the energy given out when new bonds are made in the products
  • 19. Bond energies The energy needed to break a chemical bond <ul><li>Different chemical bonds have different bond energies </li></ul>Chemical bond Bond energy, kJ/mole H―H 436 O=O 498 O―H 464
  • 20. Working out ∆H Draw an energy level diagram with all the reactants and products on it energy course of reaction 2H 2 + O 2 2H 2 O
  • 21. Working out ∆H Show all the bonds in the reactants energy course of reaction 2H 2 O H―H H―H O=O +
  • 22. Working out ∆H Show all the bonds in the products energy course of reaction H―H H―H O=O + H H O H H O
  • 23. Working out ∆H Show the bond energies for all the bonds energy course of reaction 436 436 O=O + H H O H H O
  • 24. Working out ∆H Show the bond energies for all the bonds energy course of reaction 436 436 498 + H H O H H O
  • 25. Working out ∆H Show the bond energies for all the bonds energy course of reaction 436 436 498 + 464 464 + H H O
  • 26. Working out ∆H Show the bond energies for all the bonds energy course of reaction 436 436 498 + 464 464 + 464 464 +
  • 27. Working out ∆H Add the reactants’ bond energies together energy course of reaction 464 464 + 464 464 + 1370
  • 28. Working out ∆H Add the products’ bond energies together energy course of reaction 1370 1856
  • 29. Working out ∆H ∆ H = energy in ― energy out energy course of reaction 1370 1856 1370 1856 ―
  • 30. Working out ∆H ∆ H = energy in ― energy out energy course of reaction 1370 1856 1370 1856 -486 ―
  • 31. Working out ∆H ∆ H = energy in ― energy out energy course of reaction 1370 1856 ∆ H = -486
  • 32. Working out ∆H Summary <ul><li>The energy values have units of kJ/mole </li></ul><ul><li>In the exam, you will be given the energy values and all the bonds to make or break </li></ul>∆ H is energy in – energy out <ul><li>Energy goes in to break bonds </li></ul><ul><li>Energy goes out when bonds are made </li></ul>

×