1. CHEMISTRY November 3, 2014
Electron energy

2. You have 2 minutes. You are seated and quiet Do the Science Starter

3. Why is the energy state for each electron not the same?
AIM
Why is the energy state for each electron not the same?

4. OBJECTIVES
Each electron in an atom has its own distinct amount of energy (3.1i)

5. Question
Is the energy state for each electron within an atom the same?

6. ELECTRON ENERGY
Each electron in a particular atom has a unique energy that depends on the relationship between the negatively charged electron and both the positively charged nucleus and the other negatively charged electrons in the atom.

7. ELECTRON CLOUD
The electron cloud is divided into regions called principal energy levels
Each energy level can contain up to 2n2 electron, where n is the number of the level
1st energy level = 2
2nd energy level = 8
3rd energy level = 18

8. ENERGY LEVELS
The energy associated with an energy level increases as the distance from the nucleus increase
energy level at the 2nd energy level is higher than the energy level at the 1st energy level
The lower the energy level, the harder it is to remove the electron from the atom
1s<2s<3s<4s

9. ENERGY LEVEL DIAGRAM

10. GROUND STATE
When all electrons are at their lowest possible energy state

11. ELECTRON CONFIGURATION
PERIODIC TABLE
ELECTRON CONFIGURATION

12. ELECTRON CONFIGURATION
he electron configuration of an atom is the representation of the arrangement of electrons that are distributed among the orbital shells and subshells. 

13. PERIODIC TABLE Hydrogen (1) Helium (2) Carbon (2-4) Neon (2-8)
Chlorine (2-8-7)
Lead (Pb) ( )

14. Question
Is the shape for each energy state the same?

15. ORBITALS
Electrons at a particular energy level are more likely to be found in some part of the level than in other calls orbitals
Each orbitals can contain up to 2 electrons
These electrons spin in opposite direction

16. ORBITAL SHAPES

17. ORBITAL SHAPES
These shapes do not represent the path of an electron within the atom.
It represents the region in which the electron is most likely to be found.

18. HOW TO FILL ENERGY LEVELS
Electrons fill in energy levels and orbitals starting with the one that requires the least energy (1s) and progressively move to those levels and orbitals that require increasing amounts of energy.

19. ENERGY INCREASE
For a given principal energy level:
4s<4p<4d,4f

20. Question
An orbital is defined as a region of the most probable location of
An electron
A neutron
A nucleus
A proton

21. Questions
Compared to the energy and charge of the electrons in the first shell of a Be atom, the electrons in the second shell of this atom have
Less energy and the same charge
Less energy and a different charge
More energy and the same charge
More energy and a different charge

22. Question
An atom in the ground state has two electrons in its first shell and six electrons in its second shell. What is the total number of protons in the nucleus of this atoms? 5 2 7 8

23. QUESTION
CAN AN ELECTRON MOVE FROM ONE ENERGY STATE TO ANOTHER ENERGY STATE?

24. PHOTONS
If a photon of light strikes an atom, the energy in the light may be transferred to the lower energy electrons (the energy is absorbed by the electron)
This puts the electrons into an excited state causing the electron to moves to a higher energy level.
This is an unstable situation.
The excited electron loses the extra energy (emits energy) and fall back to the lower energy level.