Module 1_Electron configuration and orbital diagram.pptx

sss

1. ELECTRON CONFIGURATION AND ORBITAL DIAGRAM

2. The module is about the electron configuration of an atom and its orbital diagram. After going through this module, you are expected to: write the electron configuration of an atom draw an orbital diagram to represent the electronic configuration of atoms recognize the importance of orbital diagram and electronic configuration of atoms. LEARNING COMPETENCY

3. PRE-TEST

4. THINK! Directions: Complete the table below. ELEMENT ATOMIC NO. ATOMIC MASS NO. OF PROTONS NO. OF ELECTRONS NO. OF NEUTRONS RADON 29 MERCURY 20 30

5. The number of electrons and how these are arranged in an atom can be used to determine the chemical properties of an atom. These are usually dependent on the atom’s number of valence electrons.

6. In the electron cloud model, we learn that electrons are arranged outside the nucleus of an atom in a compartmentalized way.

7. A representation used by chemist to denote how electrons are distributed outside the nucleus of an atom is called electron configuration .

8. The following is an example of this notation:

9. To write the electron configurations and orbital diagrams successfully, you must formulate a plan of attack and learn the following relationship:

10. The Aufbau principle states that  electrons fill lower-energy atomic orbitals before filling higher-energy ones  (Aufbau is German for "building-up"). By following this rule, we can predict the electron configurations for atoms or ions. AUFBAU’S PRINCIPLE

11. THINK! Which of the following obeys the Aufbau’s principle?

12. THINK! Which of the following obeys the Aufbau’s principle?

13. PAULI’S EXCLUSION PRINCIPLE It states that no two electrons in an atom can have the same set of four quantum numbers. This means no atomic orbital can contain more than TWO electrons and these electrons must be of opposite spin if they are to form a pair within an orbital.

14. THINK! Which of the following obeys the Pauli’s exclusion principle?

15. THINK! Which of the following obeys the Pauli’s exclusion principle?

16. HUND’S RULE It states that in the orbital of the same subshell, electrons are filled singly first before pairing starts The most stable arrangement of electrons is one with the maximum number of unpaired electrons. This minimized the electron-electron repulsions and stabilizes the atom.

17. THINK! Which of the following obeys the Hund’s rule?

18. THINK! Which of the following obeys the Hund’s rule?

19. How to write the electron configuration and draw its orbital diagram of an element: Step 1: Determine the number of electrons in the atom that needs to be distributed.

20. How to write the electron configuration and draw its orbital diagram of an element: Step 2: Bearing in mind Aufbau principle, look at the electron configuration mnemonics and proceed to distribute the electrons in the lower energy level first before moving on to the next. Keep in mind also the maximum number of electrons in each sublevel. The sum of the superscripts must be equal to the number of electrons of the atom.

21. How to write the electron configuration and draw its orbital diagram of an element: Step 3: Take in the individual configurations and draw its equivalent orbital diagram. In drawing the diagram, bear in mind the Hund’s and Pauli’s Exclusion Principles. You can do this in a more organize way by using a table.

22. A C T I V I T I E S ACTIVITY 1 TRUE or FALSE. Read the statements below. Write TRUE if the statement is correct, otherwise, write FALSE. Electron configuration distributes the valence electrons of an atom. The coefficient of a configuration denotes the energy level where the electron is found. In the configuration, 4p 3 , this means that there are 3 electrons in the p-sublevel of the 4 th energy level. According to Aufbau principle, 2p sublevel should be filled first before 2s. The electron configuration mnemonics guides us on how to fill the sublevels according to Aufbau principle. It is possible to have three electrons with different spins in one orbital. Hund’s rule state that you can already pair electrons in an orbital even though there are still orbitals that are unoccupied. In the second energy level, there are two sublevels available: s and p sublevels The d-sublevel can accommodate a maximum of 10 electrons in its orbitals. Electrons start to occupy the f-sublevel in the 4 th energy level of the atom.

23. ACTIVITY 2 Write the electron configuration of the following elements. After that, using the table presented in the examples, draw the orbital diagram of each element. Neon Potassium Cobalt Bromine Cerium

24. Writing the electron configuration and drawing the orbital diagram of an atom requires you to follow at least three principles. Can you summarize the statements under these principles? Aufbau Principle Hund’s Rule Pauli’s Exclusion Principle W R A P – U P

25. Writing the electron configuration and drawing the orbital diagram of an atom requires you to follow at least three principles. Can you summarize the statements under these principles? Aufbau Principle Hund’s Rule Pauli’s Exclusion Principle W R A P – U P