Chp 5 Atomic Structure PDF

Chp 5 (Part 2 Microscopic World I)(Updated LKC2 21/3/2023 9:06:00 AM) 1 Chp 5 Atomic structure 2 3 1. Chemical and Physical properties / change 4 1. Properties: 5 1. Physical properties: 6 1. Definition: Physical properties of a substance ar...

Chp 5 (Part 2 Microscopic World I)(Updated LKC2 21/3/2023 9:06:00 AM) 1 Chp 5 Atomic structure 2 3 1. Chemical and Physical properties / change 4 1. Properties: 5 1. Physical properties: 6 1. Definition: Physical properties of a substance are those properties that can be 7 determined without the substance changing into another substance. 8 2. Example 9 1. hardness 10 2. density 11 3. solubility 12 4. melting point 13 5. boiling point 14 6. electrical conductivity 15 7. thermal conductivity 16 2. Chemical properties: 17 1. Definition: Chemical properties of a substance are those properties that describe the 18 ability of that substance to react with other substance(s) or to change from one 19 substance to another. 20 2. Example: 21 1. Magnesium burns with oxygen vigorously to form magnesium oxide. 22 2. Baking soda reacts with vinegar to give salt, carbon dioxide and water 23 3. Alcohol burns with oxygen to give carbon dioxide and water 24 4. Sodium burns when it is added to water. 25 2. Change 26 1. Physical change 27 1. Definition: A physical change is a change in which no new substances are produced. 28 2. Example: 29 1. sublimation // deposition 30 2. condensation // boiling 31 3. freezing // melting 1  Chp 5 (Part 2 Microscopic World I)(Updated LKC2 21/3/2023 9:06:00 AM) 1 2 2. Chemical change: 3 1. Definition: A chemical change is a change in which one or more new substances are 4 produced. 5 2. Example: 6 1. When a piece of paper burns, it changes to carbon (black ashes), carbon 7 dioxide and some other gases (The products of burning are completely 8 different from the original paper.) 9 2. The elements copper and chlorine are chemically combined to form a 10 compound called copper(II) chloride (new substance). 11 3. Method 12 1. Physical method (to separate mixture into pure substances) 13 1. Definition: Physical method is a method to separate mixture into pure substances. 14 Methods used to separate mixtures rely on differences in the physical properties of 15 the components. 16 2. Example: 17 1. Mechanical separation (panning): (Gold / sand mixture)  Gold + sand 18 2. Filtration: (Sand / water)  Sand and water 19 20 3. Evaporation and Crystallization: (Salt / water)  Salt 21 4. Distillation: (Salt / water)  water 2  Chp 5 (Part 2 Microscopic World I)(Updated LKC2 21/3/2023 9:06:00 AM) 1 2 2. Chemical method (to separate compound into elements) 3 1. Definition: 4 Chemical method is a method to separate compound into element. Methods used to 5 separate mixtures rely on differences in the chemical properties of the 6 components. 7 2. Example: Method Compound Element Heating Mercury oxide  Mercury and oxygen gas Electrolysis aluminium(III) oxide  aluminium and oxygen gas 8 9 2. The relation between Properties, Change, Method: Physical properties Physical change Physical method Boiling point  Boiling  Distillation / Evaporation Solubility  dissolving  Filtration 10 Chemical properties(針對 Chemical change (動 Chemical method(應用) in 物質) of mercury oxide 作) of mercury oxide extracting mercury Heating mercury oxide can  Heating Mercury oxide  Heating Mercury oxide can produce mercury and can produce mercury produce mercury and oxygen oxygen gas and oxygen gas gas 11 12 3. Mixture, Pure substance, Element and Compound (把物質分類的第一種方法) 13 1. Mixture: 14 1. Definition: A material made up of two or more different pure substances, which are mixed 15 but are not combined chemically. 16 2. Example: Iron mixed with Sulphur 3  Chp 5 (Part 2 Microscopic World I)(Updated LKC2 21/3/2023 9:06:00 AM) 1 2. Pure substance: 2 > Definition: A pure substance is any single type of material 3 3. Element (不同類別的物質): 4 > Definition: An element is a pure substance, which cannot be broken down into anything 5 simpler by chemical methods. An element is a substance that is made up of only one kind 6 of atoms. 7 4. Compound (多於一個類別的物質結合而成): 8 > Definition: A compound is a substance formed when two or more chemical elements are 9 chemically bonded together. 10 11 Handout Question: 1. Which one is compound, element, pure substance and mixture? (After watching the video) Mercury oxide Mercury Oxygen Mercury / Aluminium 4  Chp 5 (Part 2 Microscopic World I)(Updated LKC2 21/3/2023 9:06:00 AM) https://www.youtube.com/watch?v=lkiebvwfris (Make Mercury Metal) https://www.youtube.com/watch?v=IrdYueB9pY4 (鋁汞齊) https://www.youtube.com/watch?v=-Y0v4jga9M4 (Mercury Distillation) 1 2 4. Classification of elements into metals, non-metals and semi-metals (把物質分類的 3 第二種方法) 4 Property Metals Non-metals State at room temperature Solid (except mercury a silvery Gases or solid (except bromine – a and pressure liquid) brown liquid) Appearance Shiny; mostly silvery white in Usually dull in appearance (when solid); color (except copper and gold) in various colors Melting point and boiling Usually high Usually low point Hardness and strength Hard and strong Not uniform in hardness and strength Malleability and ductility Malleable and ductile Brittle i.e. easily broken when hit (when solid); not malleable and not ductile Density Usually high Low Thermal conductivity and Good conductors of heat and Poor conductors of heat; non-conductors electrical conductivity electricity of electricity 5 6 1. Exceptional case: 7 1. Sodium is a metal. It is so soft that it can be easily cut with a knife. It is so low melting 8 that it melts below 100oC. It is so light that it floats on water. 9 2. Graphite is a non-metal. It is a good electrical conductor, shiny and has a very high 10 melting point (3730oC). 11 2. Semi-metal (metalloids): 12 1. A few elements, called semi-metals (or metalloids), have properties in between those of 13 metals and non-metals. 14 2. Examples of semi-metals: boron and silicon. 15 3. Semi-metal properties: 16 1. Semi-metals are usually brittle, shiny solids. 17 2. Semi-metals do not conduct electricity. However, when they are heated or slightly 18 impure, they conduct electricity quite well. They are semi-conductors. 5  Chp 5 (Part 2 Microscopic World I)(Updated LKC2 21/3/2023 9:06:00 AM) 1 4. Application: 2 > Silicon is a semi-conductor widely used in making computer chips. 3 3. 快速辨別金屬，非金屬，類金屬：部首 4 金屬： 金部 5 非金屬： 石部，气部 6 類金屬： 石部 7 8 5. Atom 9 原子概念： https://www.youtube.com/watch?v=8Are9dDbW24(Cosmic Eye) 10 原子動畫： https://www.youtube.com/watch?v=oSCX78-8-q0(A Boy And His Atom: The 11 World's Smallest Movie) 12 1. Atom: 13 1. Definition: An atom is the smallest part of an element, which has the chemical properties 14 of that element. 15 2. Structure of atoms: 16 1. Atoms are made up of protons, neutrons and electrons. 17 2. The protons and neutrons are concentrated in the very tiny nucleus. The electrons 18 move around the nucleus. 19 3. 20 21 4. 22 23 3. Electrically neutral: 24 1. An atom is electrically neutral because in the atom, the number of protons is equal to the 25 number of electrons. 6  Chp 5 (Part 2 Microscopic World I)(Updated LKC2 21/3/2023 9:06:00 AM) 1 6. Chemical symbols for elements 2 1. The relationship between atom and element: Pure substance Compound(多於一個類別的物質 Element (不同類別的物質)： 結合而成) 1. Iron 類別 2. Sulphur 類別 3. hydrogen 類別 4. helium 類別 5. oxygen 類別 根據質子數目的不同而變成不 同元素的物質 3 Atomic structure Proton number Element > 1 Hydrogen > > 2 Helium > > 26 Iron 7  Chp 5 (Part 2 Microscopic World I)(Updated LKC2 21/3/2023 9:06:00 AM) > 1 2 Element Symbol Atomic No. of Electronic Stable ? number electrons arrangement 1 Hydrogen 氫 H 1 1 1 No 2 Helium 氦 He 2 2 2 Yes 3 Lithium 鋰 Li 3 3 2, 1 No 4 Beryllium 鈹 Be 4 4 2, 2 No 5 Boron 硼 B 5 5 2, 3 No 6 Carbon 碳 C 6 6 2, 4 No 7 Nitrogen 氮 N 7 7 2, 5 No 8 Oxygen 氧 O 8 8 2, 6 No 9 Fluorine 氟 F 9 9 2, 7 No 10 Neon 氖 Ne 10 10 2, 8 Yes 11 Sodium 鈉 Na 11 11 2, 8, 1 No 12 Magnesium 鎂 Mg 12 12 2, 8, 2 No 13 Aluminium 鋁 Al 13 13 2, 8, 3 No 14 Silicon 硅 (矽) Si 14 14 2, 8, 4 No 15 Phosphorus 磷 P 15 15 2, 8, 5 No 16 Sulphur 硫 S 16 16 2, 8, 6 No 17 Chlorine 氯 Cl 17 17 2, 8, 7 No 18 Argon 氬 Ar 18 18 2, 8, 8 Yes 19 Potassium 鉀 K 19 19 2, 8, 8, 1 No 20 Calcium 鈣 Ca 20 20 2, 8, 8, 2 No 3 4 Handout Question: Proton number Element 8  Chp 5 (Part 2 Microscopic World I)(Updated LKC2 21/3/2023 9:06:00 AM) 1 12 2 Fluorine 3 56 4 101 5 Vanadium 6 5 1 2 7. Electronic arrangement of atoms (Up to Z = 20) 3 4 5 1. electronic arrangement (or electronic configuration) of a sodium atom is 2, 8, 1 6 2. The electron diagram of a sodium atom is: 7 8 3. Handout Question: Electronic Electronic Number of Proton Element arrangement diagram 3 9  Chp 5 (Part 2 Microscopic World I)(Updated LKC2 21/3/2023 9:06:00 AM) Silicon 8 19 Calcium 1 4. 從實驗觀察上，我們得知氦，氖，氬，氪，氙比其他的元素更穩定。而我們發現氦，氖， 2 氬，氪，氙的電子排佈有特別的模式 Element Electronic arrangement 1 Helium 2 2 Neon 2,8 3 Argon 2,8,8 4 Krypton 2,8,18,8 5 Xenon 2,8,18,18,8 3 1. The stability of noble gases is related to their electronic arrangements. 4 2. Very Important: 5 元素的化學性質主要受最外層電子數目所影響。 6 Chemical properties of an element depend mainly on the number of outermost shell 7 electrons. 8 3. Octet rule: 10  Chp 5 (Part 2 Microscopic World I)(Updated LKC2 21/3/2023 9:06:00 AM) 1 Definition: The strong tendency of all atoms to attain the stable electronic arrangement of 2 a noble gas (in most cases an octet) 3 The name to describe the special electron structure: 4 1. an octet of electrons = 8 electrons in the outermost shell 5 2. a duplet of electrons = 2 electrons in the only one occupied shell 6 7 8. Atomic number and mass number 8 1. Atomic number (Z) of an atom = number of protons in the atom 9 2. Mass number (A) of an atom = number of protons + number of neutrons in the atom 10 11 12 9. Isotopes 13 1. Isotopes: 14 Definition: Isotopes are different atoms of the same element, with the same number of protons 15 but different numbers of neutrons. 16 17 18 11  Chp 5 (Part 2 Microscopic World I)(Updated LKC2 21/3/2023 9:06:00 AM) 1 2 3 2. Physical properties of isotope: 4 1. They have different numbers of neutrons. They have different masses and hence slightly 5 different physical properties. 6 2. Example: melting point 35Cl-35Cl < 37Cl-37Cl 7 3. Chemical properties of isotope: 8 1. Isotopes of the same element have the same number of protons and electrons in their atoms 9 2. Isotopes have the same electronic arrangement. 10 3. Isotopes have the same number of electrons in outermost shell. 11 4. Isotopes have the same chemical properties. 12 13 9. Relative isotopic mass and relative atomic mass 14 1. Relative isotopic mass: (針對某一種同位素) 15 1. Definition: Relative Isotopic Mass is the mass of an isotope relative to the mass of 16 Carbon-12 = 12 units. 17 2. 明白的概念： 18 Relative isotopic mass = mass number (在數值上是一樣，但意義上是絕無關係) Mass number Relative isotopic mass 35-Cl 37-Cl 79-Br 81-Br 19 2. The relative atomic mass: 20 1. Definition: The relative atomic mass of an element is the weighted average of the relative 21 isotopic masses of its natural isotopes on the 12C=12 scale. 22 2. 計算方法： For an element consisting of three isotopes A, B and C: 23 Relative atomic mass = (A% x Ma) + (B% x Mb) + (C% x Mc) 24 A%, B%, C% = relative abundance of isotopes A, B, C 豐度百分 12  Chp 5 (Part 2 Microscopic World I)(Updated LKC2 21/3/2023 9:06:00 AM) 1 比 2 Ma, Mb, Mc = relative isotopic masses of isotopes A, B, C 同位 3 素的相對同位素質量 4 3. Handout Question: Isotope Mass Relative Relative Isotope Mass Relative Relative Relative 1 number Isotopic abundance 2 number Isotopic abundance atomic Mass Mass mass Chlorine 35-Cl 75% 37-Cl 25% Cl atom Cl atom = Bromine 79-Br 81-Br Br atom Br atom = 79.9 5 6 4. Example: 7 8 **請提醒老師要和學生完成書中的 Example，Self-test， 9 Class practice，Chapter exe，Exam practice，最少也需要 10 向同學講解不同題型處理方法。** 11 13