2Q Lesson 1 - Introduction to Valence Electrons and Bonding AY2024-2025 PDF

RECALL ACTIVITY Directions: Read the definition found on the concept map then complete the concept map by providing the correct terms. Materials: Pen and paper per group Level 1: Group Task (All members of the group will work collaboratively to complete the activity)  REVIEW...

RECALL ACTIVITY Directions: Read the definition found on the concept map then complete the concept map by providing the correct terms. Materials: Pen and paper per group Level 1: Group Task (All members of the group will work collaboratively to complete the activity)  REVIEW MATTER 1.anything that occupies space and has mass PURE SUBSTANCE MIXTURE 2. Any matter 3. combinations of two or more pure substances in variable that has a fixed chemical proportions in which the composition and characteristic individual substances retain properties their identity ATOM ELEMENT COMPOUND MOLECULE HETEROGENOUS 5. a 6. a HOMOGENOUS 4. a particle substance substance 8. 9. of matter that that cannot made from 7. a group of combinations composition uniquely be broken two or more two or more of two or more of a material defines a down into different atoms held pure is not chemical any other elements together by substances in completely element. substance that have chemical variable uniform been bonds. proportions in chemically which the joined. individual substances retain their identity RECALL ACTIVITY Directions: Determine whether the figure represents an atom, molecule, compound, or mixture. Materials: White board marker per group Level 2: Group Representative (All members of the group will work collaboratively but only one member will answer on the board to complete the activity) ATOM COMPOUND MOLECULE COMPOUND MOLECULE ATOM MIXTURE RECALL ACTIVITY Directions: Determine whether the term represents an element, molecule, compound, or mixture. Materials: White board marker per group Level 3: Individual Task (A member from each group will answer on the board to complete the activity)  Gold (Au) ELEMENT Oxygen gas (O2) MOLECULE  Water (H2O) COMPOUND  Air MIXTURE  Nitrogen gas (N2) MOLECULE  Carbon dioxide (CO2) COMPOUND  NaCl solution MIXTURE  Neon (Ne) ELEMENT REVIEW Chapter 1: Atomic Structure a n d Va l e n c e Electrons Lesson 1: Introduction to Valence Electrons and Bonding  Learning Target: I can explain the I can identify I can develop an appreciation for the role concept of valence their valence of valence electrons in electrons and their significance in electrons using chemical reactions and bonding, fostering a chemical bonding. quantum deeper interest in numbers. chemistry.  Part I. ATOMIC STRUCTURE  NEILS BOHR Erwin Schrödinger PLANETARY MODEL QUANTUM MECHANICAL MODEL NIELS BOHR – QUESTIONS RAISED How is an electron distributed in an atom? What is the maximum number of electrons in an energy level? How are electrons arranged in an energy level?  NEILS BOHR Erwin Schrödinger PLANETARY MODEL QUANTUM MECHANICAL MODEL Accurately describes how electrons Oversimplifies how electrons behave. behave. Electrons exist in regions of Depicts electrons as orbiting the probability called orbitals, which nucleus in fixed paths, like planets better match experimental around the sun, which isn’t accurate. observations and the principles of quantum mechanics. KEYWORD S: Valence Shell Valence Electron Electron Configuration  ATOM ATOMIC NUMBER smallest unit No. of protons of matter no. of = electrically protons in No. of electrons neutral the nucleus of an atom Element: Nitrogen Atomic no.: 7 No. of Protons: 7 No. of Electrons: 7 BOHR MODEL Shells can hold up to... 1st shell = 2e- 2nd shell = 8e- 3rd shell = 18e- 4th shell = 32e- BOHR MODEL Max. no. of e- in a shell can be given by the formula 2𝑛². Hence… 1st shell = 2(1)² = 2e- 2nd shell = 2(2)² = 8e- 3rd shell = 2(3)² = 18e- 4th shell = 2(4)² = 32e-  VA L E NCE S HE L L Outermost shell of an atom containing valence electrons VAL E NCE E L EC TRO NS Electrons in the outermost shell and participate in chemical reactions CO R E E L EC TRO NS Electrons that do not participate in chemical bonding. BOHR MODEL Valence electrons = 5 Core electrons =2 TOTAL e- 7 TRY IT! Atomic 13 number No. of p+ 13 Al No. of e- 13  GUIDE: (up to…) 1st shell = 2e- 2nd shell = 8e- 3rd shell = 18e- Al Valence electrons = 3 Core electrons = 10 TOTAL e- 13  GUIDE: (up to…) 1st shell = 2e- 2nd shell = 8e- 3rd shell = 18e- Na Valence electrons = 1 Core electrons = 10 TOTAL e- 11  REVIEW 1. What is an atom? 2. What is the charge of an atom? 3. What are the subatomic particles? 4. How do we get the number of electrons of an atom?  REVIEW 5. Differentiate planetary model and quantum mechanical model. 6. Define valence shell Al and valence electrons. 7. These are the electrons that participate in chemical reactions.  How many electrons can each shell hold? 1st shell = 2e- 2nd shell = 8e- 3rd shell = 18e- Al 4 th shell = 32 e- Valence electrons = 3 Core electrons = 10 TOTAL e- 13 Total e- = 26 Valence e- = 8 1 st shell = 2e- 2 nd shell = 8e- 3 rd shell = 14e- 4 th shell = 2e-  Part II. E L EC TRO N CON FIGURATION - the arrangement of electrons in orbitals around the atomic nucleus.  SUBLEVELS can only hold: s = 2 e- p = 6 e- d = 10 e- f = 14 e- ANSWER: EL EC T RO N DIST RIB U T IO N M NEM O NICS Level 1 has 1 sublevel (s) Level 2 = 2 sublevels (s, p) Level 3 = 3 sublevels (s, p, d) Level 4 = 4 sublevels (s, p, d, f) Sublevels/ subshells Energy level/Shell SUBLEVELS (subshells) can only hold 2 electrons per orbital: s = 1 orbital = 2 e- p = 3 orbitals = 6 e- d = 5 orbitals = 10 e- f = 7 orbitals = 14 e- SUBLEVELS (subshells) can only hold 2 electrons per orbital: Houses in Subshell Street s = 1 orbital = 2 e- p = 3 orbitals = 6 e- d = 5 orbitals = 10 e- f = 7 orbitals = 14 e- f s p d Energy level No. of electrons in each subshell Subshell/ sublevel AUFBAU PRINCIPLE - Electrons fill atomic orbitals of the lowest available energy levels before occupying higher levels. 1s 2s 3s 4s 5s 6s 7s 2p 3p 4p 5p 6p 7p 3d 4d 5d 6d 7d 4f 5f 6f 7f Si Susan Pumasok Sa Pinto Si Daddy Pumasok Sa Door Paano Si Frank, Daddy? Paano Si Frank, Daddy? Paano?  SUBLEVELS can only hold: s = 2 e- p = 6 e- d = 10 e- f = 14 e- ANSWER:  SUBLEVELS can only hold: s = 2 e- p = 6 e- d = 10 e- f = 14 e- ANSWER: TRY IT! SUBLEVELS can only hold: s = 2 e- p = 6 e- d = 10 e- f = 14 e- ANSWER: TRY IT! SUBLEVELS can only hold: s = 2 e- p = 6 e- d = 10 e- f = 14 e- ANSWER: TRY IT! SUBLEVELS can only hold: s = 2 e- p = 6 e- d = 10 e- f = 14 e- ANSWER:  SUBLEVELS can only hold: s = 2 e- p = 6 e- d = 10 e- f = 14 e- ANSWER:  REVIEW 1 2 3 How do you What is What is identify the electron valence valence configuration electron? electrons of ? elements?  REVIEW 1 2 Shells can hold up to... SUBLEVELS (subshells) can only hold 2 electrons 1st shell = 2e- per orbital: 2nd shell = 8e- s = 1 orbital = 2 e- 3rd shell = 18e- p = 3 orbitals = 6 e- 4th shell = 32e- d = 5 orbitals = 10 e- f = 7 orbitals = 14 e- Part III. QUANTUM NUMBERS  QUANTUM NUMBERS Quantum numbers describe the location of an electron in a three-dimensional atom. Angular Principal Magnetic Momentum Spin Quantum Quantum Quantum Quantum Number (ms) Number (n) Number (m1) Number (l)  Principal Quantum Number (n) It specifies the main energy n level occupied by the electron. It is also called as shell. 1 2 It is represented by a whole number, with (n) starting at 3 1 for the energy level closest to the nucleus, 4 followed by (n = 2), and (n = 3) for levels farther away.  l n Angular Momentum Quantum Number (l) (n – 1) 1 0 It describes the general region occupied by the electron called 0 2 subshell or orbital. 1 Every energy level has one or more 0 than one subshell. 3 1 The subshell is denoted by an integer that starts from 0 up to the 2 value equal to n - 1. 0 This quantum number is also called 1 4 Azimuthal quantum number and 2 represented by l. 3  l Angular Momentum n Orbital Quantum Number (l) (n – 1) 1 0 s Therefore, 0 s If n = 1 only has s 2 1 p subshell 0 s If n = 2 it has s and p subshells 3 1 p If n = 3 it has s, p, and 2 d d subshells 0 s If n = 4 it has s, p, d, 1 p and f subshells 4 2 d 3 f Angular Momentum l n Orbital Quantum Number (l) (n – 1) 1 0 s 0 s 2 1 p 0 s 3 1 p 2 d 0 s 1 p 4 2 d 3 f Self-Check: 1. What is the angular momentum quantum number (l) of n=3? 2. What are the subshells/orbitals in n=4? Angular Momentum Quantum Number (l) Each value of angular momentum quantum number shows the possible directions where electrons may move in a three- dimensional atom causing different shapes of orbital. l Orbital (n – 1) 0 s 1 p 2 d 3 f Electrons move in specific regions: For 1st energy level only the gray area For 2nd energy level s orbital the red area For 2nd energy level p orbital the orange area either on x, y, or z axis  Where is the valence electron of carbon likely located? Energy Angular level/shell/ # of e- Momentum Principal Subshell/ per # of e- Quantum Quantum Orbital subshell/ per shell Number Number orbital Number of (l) (n) electron 1 0 s 2 2 0 s 2 4 6 2 1 p 2 (valence e-) 1s2 2s2 2p2 Total = 6  Where is the valence electron of carbon likely located? Energy Angular level/shell/ # of e- per Momentum Subshell/ # of e- per Principal subshell/ Quantum Number Orbital shell Quantum Number orbital (l) (n) 1 0 s 2 2 Number of electron 0 s 2 2 8 1 p 6 0 s 2 13 3 1 p 1 3 (valence e-) 2 d 0 Total = 13  Magnetic Quantum Number (ml) It describes the orbital l M1 orientation of the n (n – 1) (2l + 1) electron in space. It is dependent on angular momentum 1 0 1 0 quantum number. 2 1 3 -1, 0, 1 In each subshell, the number of orbitals is 3 2 5 -2, -1, 0, 1, 2 given by (2l + 1), and its value ranges from 4 3 7 -3, -2, -1, 0, 1, 2, 3 (-l) to (+l), including 0.  Magnetic Quantum Number (m1) l M1 n (n – 1) (2l + 1) 1 0 1 0 2 1 3 -1, 0, 1 3 2 5 -2, -1, 0, 1, 2 4 3 7 -3, -2, -1, 0, 1, 2, 3  Magnetic Quantum Number (m1) It is used to identify each electron in an atom s= l 0 p= l -1 0 1 d= l -2 -1 0 1 2 f= l -3 -2 -1 0 1 2 3  Spin Quantum Number (ms) It describes the spin for a given ↑ ↑ ↑ electron. Electron spin (s = ½) can take 2p3 only two orientation with respect to a specified axis If an electron (spin up) is an electron with +1/2 (it denoted as ↑) ↑↓ ↑ ↑ If an electron (spin down) is an electron with −1/2 (it 2p4 denoted as ↓) Hund’s Rule Electrons fill each orbital singly Pauli Exclusion with the same spin before pairing up. Principle No two electrons in an atom can have the same set of ↑ ↑ ↑↓ ↑ ↑ four quantum numbers. This means that an orbital can -1 0 1 -1 0 1 hold a maximum of two electrons, and they must 2p2 2p4 have opposite spins.  Two electrons per orbital moving in opposite Spin Quantum Number (ms) directions. s= ↑↓ l 0 p= ↑↓ ↑↓ ↑ ↓ l -1 0 1 d = ↑↓ ↑↓ ↑↓ ↑↓ ↑↓ l -2 -1 0 1 2 f= ↑↓ ↑↓ ↑↓ ↑↓ ↑↓ ↑↓ ↑↓ l -3 -2 -1 0 1 2 3  Where is the valence electron of carbon likely located? Electron Configuration 1s2 2s2 2p2 Principal Quantum Number (n) 2 Angular Momentum Quantum Number 1 (l) Magnetic Quantum Number (m1) 0 Number of Spin Quantum Number (ms) 1/2 electron m1 = 0 0 -1 0 1 6 ↑↓ ↑↓ ↑ ↑ 1s2 2s2 2p2 ms = +1/2 -1/2 +1/2 -1/2 +1/2 +1/2 Using quantum numbers, what is the orientation of the last electron in a carbon atom? Number of electron n l ml ms 6 2 1 0 1/2  2 Self-Check n I AMQN ml orbital # of electrons (2l + 1) (n - 1) 3 Electron Configuration: 1 Electron Configuration Illustration: Symbol # of p+ # of e- 4 5 6 Symbol # of ve- n l ml ms Self-Check 2 AMQN # of ml n I # of electrons orbital electrons (2l + 1) (n - 1) per orbital per shell 0 1 0 S 2 2 (1) 0 s 2 -1, 0, 1 2 8 1 p 6 (3) 0 s 2 1 3 1 p 6 8 -2, -1, 0, 1, 2 # of (5) Symbol # of e- p+ 2 d 0 0 s Last electron Ca 20 20 2 1 p 0 -3, -2, -1, 0, 1, 2, 3 4 2 2 d 0 (7) 3 f 0 3 Electron Configuration: 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² Self-Check 3 4 Electron Configuration Illustration: Last electron m1 = 0 0 -1 0 1 0 -1 0 1 0 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² Spin down ms = -1/2 Self-Check 5 n l ml ms 4 0 0 -1/2 6 Symbol # of ve- Ca 2 Self-Check 2 AMQN # of ml n I # of electrons orbital electrons (2l + 1) (n - 1) per orbital per shell 0 1 0 S 2 2 (1) 0 s 2 -1, 0, 1 1 2 1 p 6 8 (3) # of Symbol # of e- p+ 0 s 2 -2, -1, 0, 1, 2 3 1 p 7 Cl 17 17 5 (5) 2 d 0 Electron Configuration: 1s² 2s² 2p⁶ 3s² 3p5 3 Self-Check 3 4 Electron Configuration Illustration: Last electron m1 = 0 0 -1 0 1 0 -1 0 1 1s² 2s² 2p⁶ 3s² 3p5 Spin up ms = 1/2 Self-Check 5 n l ml ms 3 1 1 1/2 6 Symbol # of ve- Cl 7 Part IV. PERIODIC TABLE PERIOD - horizontal row ofchemical elements - As you move from left to right across a period, elements become less metallic and more non- metallic PERIOD 1 – colorless gases; have electrons on the 1st shell only (s orbital) PERIOD 2 – contains 8 elements; electrons fill the 2nd shell; follow the octet rule PERIOD 3 – electrons fill the 3rd shell (s and p orbitals); follow the octet rule PERIOD 4 – contains 18 elements; val. e- in the 4s, 3d, 4p orbitals PERIOD 5 – contains 18 elements; val. e- in the 5s, 4d, and 5p orbitals PERIOD 6 – contains 32 elements including lanthanides; val. e- in 6s, 4f, 5d and 6p orbitals; contains lead (Pb) which is the heaviest stable element PERIOD 7 – contains 32 elements including actinides; val e- in 7s,5f,6d, 7p orbitals GROUP NUMBER - vertical columns in the periodic table that indicate the number of valence electrons for main group elements GROUP 1 – HYDROGEN AND ALKALI METALS GROUP 2 – ALKALINE EARTH METALS GROUP 3 – TRANSITION METALS GROUP 4 – TRANSITION METALS GROUP 5 – TRANSITION METALS GROUP 6 – TRANSITION METALS GROUP 7 – TRANSITION METALS GROUP 8 – TRANSITION METALS GROUP 9 – TRANSITION METALS GROUP 10 – TRANSITION METALS GROUP 11 – TRANSITION METALS GROUP 12 – METALS GROUP 13 – BORON GROUP GROUP 14 – CARBON GROUP GROUP 15 – NITROGEN GROUP GROUP 16 – OXYGEN FAMILY GROUP 17 – HALOGENS GROUP 18 – NOBLE GASES s and p blocks are representative elements d block contains transition metals f block contains the inner transition metals/lanthanide and actinide series of elements s- Block Elements Elements in Groups 1 and 2 where the number of valence electrons equals the group number p-Block Elements elements in Groups 13 to 18 where the number of valence electrons is the group number minus ten. d-Block Elements Transition metals where valence electrons include those in the outermost s and d subshells.  REVIEW JUMBLED LETTERS Electrons in the outermost shell of an atom that are involved in chemical bonding. LENEVAC CRNTEELSO VALENCE ELEC TRONS A tabular arrangement of elements b a s e d o n t h e i r a t o m i c n u m b e r, electron configurations, and recurring chemical properties. IICEOPDR L ABTE PERIODIC TABLE The vertical columns in the periodic table that indicate the number of valence electrons for main group elements. UGORP EMUNRB GROUP NUMBER  The distribution of electrons in an a t o m ’s o r b i t a l s , w h i c h h e l p s d e t e r m i n e the number of valence electrons. NRTCEOEL GACNIOTIURONF ELEC TRON CONFIGURATION Elements in Groups 1 and 2, where the number of valence electrons e q u a l s t h e g r o u p n u m b e r. KLOCB-S TELSMENE s -block elements Elements in Groups 13 to 18, where the number of valence electrons is the group number minus ten. P-KBLCO NTLSMEEE p-block elements  Elements in the d-block, where valence electrons include those in the outermost s and d subshells. SNNTTOIRIA SETL AM Transition Metals A rule that electrons occupy the lowest energy orbitals first. UBFUAA NPRICEPIL Aufbau Principle Electrons fill orbitals singly with the same spin before pairing up. HUNSD LEUR Hund’s Rule  No two electrons in an atom can have the same set of four quantum numbers. PUL AI XSCNUOIEL EIRIPPLNC Pauli Exclusion Principle T H A N K YO U ! Feel free to email me at [email protected] if you have questions.  Energy Subshell/ Max # of e- Max # of e- level/shell orbital per subshell per shell 1 s 2 2 s 2 2 8 p 6 s 2 3 p 6 18 d 10 s 2 p 6 4 32 d 10 f 14 SUBLEVELS (subshells) can only hold 2 electrons per orbital: Houses in Subshell Street s = 1 orbital = 2 e- p = 3 orbitals = 6 e- d = 5 orbitals = 10 e- f = 7 orbitals = 14 e- f s p d To answer the question what is the maximum number of electrons per energy level  ATOMIC STRUCTURE Number of Energy Subshell/ electron # of e- per # of e- per level/shell Orbital subshell shell (n) (l) 6 1 s 2 2 s 2 2 4 p 2 total 6  QUANTUM NUMBERS Quantum numbers describe the location of an electron in a three-dimensional atom. Angular Principal Magnetic Momentum Spin Quantum Quantum Quantum Quantum Number (ms) Number (n) Number (m1) Number (l) SEATWORK ELEMENT ELECTRON NO. OF CONFIGURATI VALENCE 1 Ne ON ELECTRONS Give the electron 1. Ne 2 S configuration and no. of valence electrons 2. S 3 V of the following 3. V elements: 4 Fe 4. Fe Points: 5 Cu No. of valence e-= 1 5. Cu e- configuration = 3