Science Grade 9 Week 2 Quarter 2 PDF

Tab 1 Science GRADE 9 2nd QUARTER - Democritus called these I'll W2: The Electron Structure of Matter objects “atomos” = uncuttable - He imag...

Tab 1 Science GRADE 9 2nd QUARTER - Democritus called these I'll W2: The Electron Structure of Matter objects “atomos” = uncuttable - He imagined that the atoms came in different sizes and TOPIC OVERVIEW shapes A. Timelines of Atomic Models A2 Dalton's Model of the Atom(1808) a. Early Ideas b. Dalton's Model c. Plum Pudding Model John Dalton - British Scientist d. Nuclear Model Matter consist of indivisible atoms e. Bohr Model Atoms arrange in different combinations f. Quantum Mechanical Model to make different compounds B. The Uncertain Location of Electrons a. Atoms A3 Plum Pudding Model(1904) b. Orbitals C. Quantum Numbers, Atomic Orbitals, J.J. Thompson and Electron Configuration Atoms are made up of different electrons a. Quantum Numbers which are much smaller b. Electron Configuration Negative electrons(plum) stuck in a positively charged “dough” They are balanced so it's electrically neutral A Timelines of Atomic Models A4 Nuclear Model(1911) Tackles the subatomic particles - Nucleus, proton, electron Ernest Ritherford Gold foil experiment Additional Information Atoms had a nucleus, all the positive Include any extra details in this section. charge of an atom was concentrated on the center Besides nucleus and electrons, atoms A1 Early Ideas about Atoms were pretty much empty space 2500 years ago Democritus and Leucippus - First people to talk about the A5 Bohr Model(1913) idea of atoms - Imagine you cut down an Niels Bohr object and you cut that half in Also has nucleus like the Nuclear model half, eventually you're going to vut the electrons are sort of being come to something that you randomly distributed throughout the atom can't cut in half The electrons are like planets spinning around the nucleus PAGE 1 GRADE 9 SIRIUS – S.Y. 2024-2025 Science GRADE 9 2nd QUARTER B2 Orbitals A6 Quantum Mechanical Model(1920s) Three dimensional description of the most likely location of an electron around Erwin Schrödinger an atom. Instead of the atoms spinning/orbiting There are 4 types of orbitals, s, p, d, and f. around the nucleus it was buzzing The more energy an orbital has, the around the atoms, sketching out further most of its density is from the different shapes nucleus. Quantum Mechanical Model with Past a certain distance from the nucleus, Protons + Neutrons the probability of finding an electron - Scientists discovered that 2 starts to decrease. subatomic particles made up the nucleus, which are; a. Protons: Ernest Rutherford(1919) b. Neutrons: James Chadwick(1932) C Quantum Numbers, Atomic Orbitals, and Electron Configuration Location and energy of every electron in an atom is determined by a set of 4 B The Uncertain Location of an Electron quantum number that describe different atomic orbitals There are s, p, d, and f orbital with Cores of an atom tend to stick together different shapes. They are the regions of Electrons are free to move around space where electrons can be. - We can't exactly say where they are - There is a certain probability that C1 Quantum Numbers we can find an electron in given space around the nucleus 1. Principal Quantum Number - n=1,2,3… B1 Atoms - Represents the energy level of electrons - The larger the value of the orbital, the further away from nucleus Core of an atom or nucleus consist of; - At least 1 proton 2. Angular Momentum Quantum Number - At some cases have some neutron - l=0,1,2,3… (n-1) - It describes the shape of the orbital Have electrons around them - surrounds - ex1: if electron has n value of 3, either 0, 1, the core or 2 is the value of l because, Atoms can give up their electrons or share their electrons to other atoms n=3 l = 3-1 so l = 0,1,2 - When l = 0, it is s-orbital - When l = 1, it is p-orbital PAGE 2 GRADE 9 SIRIUS – S.Y. 2024-2025  Science GRADE 9 2nd QUARTER - When l = 2, it is d-orbital 1. S orbitals - 1 value that contains 2 electrons - When l = 0, it is f-orbital 2. P orbitals - contains 3 values with 2 electrons 3. Magnetic Quantum Number each, total of 6 electrons - ml = -l…l 3. D orbitals - contains 5 - If l=2 then; values with 2 electrons ml = -2, -1, 0, 1, 2 each, total of 10 electrons 4. F orbitals - contains 7 - This quantum number determines how values with 2 electrons many orbitals there sre of a type per each, total of 14 electrons energy level - Therefore describes a specific orbital amongst a particular set 4. Spin Quantum Number - ms = +½ or -½ - Every electron has a unique set of quantum numbers so no 2 electrons in an atom can have precisely the same value for all four quantum numbers as stated by Pauli Exclusion Principle. - This is because any orbital can only hold up to 2 electron even the two electron in the same exact orbital will have opposite spin value - example: Hund’s Rule - For electrons of the same energy, you put one electron in each C2 Electron Configuration orbital first before doubling them up. Aufbau Principle - Example: Chlorine (Cl, 17) - Tells us the order in which an - It has a total of 17 electrons atom will fill up its orbitals Electron configuration: - This is determined by their 1s²2s²2p⁶3s²3p⁵ relative energy Why is 3p only 5, not 6? - Starts from lower energy PAGE 3 GRADE 9 SIRIUS – S.Y. 2024-2025 Science GRADE 9 2nd QUARTER - Based on aufbau Principle and hund’s rule: - ml = specific orbital 17-2(1s)-2(2s)-6(2p)-2(3s)-5(3 - ms = spin p)=0 - an atom will fill up orbitals with electrons according to the aufbau - So in 3p, it was like this principle until all of this electrons have a place to stay - since there are only 5 electrons left, the third orbital wouldn't double - Abbreviation: [Ne]3s²3p⁵(uses noble gasses) Orbital Diagram - Atoms with unpaired electrons in orbital diagrams are called paramagnetic and are attracted by a magnetic field - Ex. F - Atoms with all their electron paired are diamagnetic and are not affected by a magnetic field - Ex. Ne Summary - n = energy level - l = orbital type PAGE 4 GRADE 9 SIRIUS – S.Y. 2024-2025 Tab 2