Electron Energy Level Notes

1. Electron Energy Level Notes Electron Configuration pgs 146 - 161

2. Warm up Use your understanding of chemistry to explain: Why is this funny? Have last nights HW out for a stamp. Period 1 – vocab too!

3. Last night’s HW highlights 13. Ionization Energy 14. Charge on alkaline earth metals? 22. Why transitions can have more than one charge? 24. similar properties to gold? 51. F is most electronegative 57. Noble gases – high ionization energy

4. Ferocious Elements • https://www.stem.org.uk/elibrary/resource/30887

5. Essential Questions and Objectives • How does the configuration of electrons effect the atom’s properties? You’ll be able to: • Draw an orbital diagram for an element • Determine the electron configuration for an element • Explain the Pauli exclusion principle, Aufbau principle and Hund’s Rule

6. Quantum Mechanical Model • Electrons do not travel around the nucleus of an atom in orbits • They are found in energy levels at different distances away from the nucleus (kind of like shells or layers) in orbitals • Orbital – region in space where there is a high probability of finding an electron.

7. Quantum Mechanical Model The wave function predicts a three-dimensional region around the nucleus called the atomic orbital.

8. Atomic Orbitals Electrons cannot exist between energy levels (just like the rungs of a ladder). Principal quantum number (n) indicates the relative size and energy of atomic orbitals. n specifies the atom’s major energy levels, called the principal energy levels.

9. Atomic Orbitals continued • Energy levels are broken up into sublevels: • There are at least 4 possible types of sublevels—given labels: s, p, d, or f Where have we heard “s, p, d, f” before?

10. Energy sublevels are contained within the principal energy levels.

11. Orbital shapes

12. Ground-State Electron Configuration The arrangement of electrons in the atom is called the electron configuration.

13. Your group’s task: GOAL: Use the orbital diagram to show the electron configuration of your element. • Record the definitions of each rule or principle in you notes. • Match the rule or principle with the example and nonexample card. • Use the three rules as your guide to come up with the electron configuration for the electrons in your assigned atom. You will present your group’s findings to the class.

15. Orbital Filling • The order that electrons fill up orbitals does not follow the logical order of all 1’s, then all 2’s, then all 3’s, etc. • They follow the order found on the periodic table!

16. Use the Periodic Table! • An easy way to remember this is to use the periodic table--it is arranged to show how these orbitals are filled.

17. Order of Orbitals—Periodic Table

18. Practice Work on the Electron Configuration ½ sheet. Check in for answers. Complete for HW Have an awesome LONG weekend!

19. Hund’s rulestates that single electrons with the same spin must occupy each degenerate orbital before additional electrons with opposite spins can occupy the same energy level orbitals.

20. Hund’s rulestates that single electrons with the same spin must occupy each degenerate orbital before additional electrons with opposite spins can occupy the same energy level orbitals.

21. Hund’s rulestates that single electrons with the same spin must occupy each degenerate orbital before additional electrons with opposite spins can occupy the same energy level orbitals.

22. Hund’s rulestates that single electrons with the same spin must occupy each degenerate orbital before additional electrons with opposite spins can occupy the same energy level orbitals.

23. Hund’s rulestates that single electrons with the same spin must occupy each degenerate orbital before additional electrons with opposite spins can occupy the same energy level orbitals.

24. Hund’s rulestates that single electrons with the same spin must occupy each degenerate orbital before additional electrons with opposite spins can occupy the same energy level orbitals.

25. The Pauli exclusion principle states that a maximum of two electrons can occupy a single orbital, but only if the electrons have opposite spins.

26. The Pauli exclusion principle states that a maximum of two electrons can occupy a single orbital, but only if the electrons have opposite spins.

27. The Pauli exclusion principle states that a maximum of two electrons can occupy a single orbital, but only if the electrons have opposite spins.

28. The Pauli exclusion principle states that a maximum of two electrons can occupy a single orbital, but only if the electrons have opposite spins.

29. The Pauli exclusion principle states that a maximum of two electrons can occupy a single orbital, but only if the electrons have opposite spins.

30. The Pauli exclusion principle states that a maximum of two electrons can occupy a single orbital, but only if the electrons have opposite spins.

31. The aufbau principle states that each electron occupies the lowest energy orbital available.

32. The aufbau principle states that each electron occupies the lowest energy orbital available.

33. The aufbau principle states that each electron occupies the lowest energy orbital available.

34. The aufbau principle states that each electron occupies the lowest energy orbital available.

35. The aufbau principle states that each electron occupies the lowest energy orbital available.

36. The aufbau principle states that each electron occupies the lowest energy orbital available.

37. Section 5-3 Ground-State Electron Configuration (cont.)

38. Ground-State Electron Configuration (cont.) Noble gas notation uses noble gas symbols in brackets to shorten inner electron configurations of other elements.

39. Ground-State Electron Configuration (cont.) The electron configurations (for chromium, copper, and several other elements) reflect the increased stability of half-filled and filled sets of s and d orbitals.

40. Practice • What is the electron configuration of … • Hydrogen? • Helium? • Lithium?

41. Valence Electrons Valence electronsare defined as electrons in the atom’s outermost orbitals—those associated with the atom’s highest principal energy level. Electron-dot structureconsists of the element’s symbol representing the nucleus, surrounded by dots representing the element’s valence electrons.

42. Valence Electrons (cont.)