General Chemistry Lecture Notes PDF

B R I C KS N OT ES |1 MODULE 1: GENERAL CHEMISTRY Main types: Lecture by John Mitchell L. Lua Þ SmecEc – soap-like/grease-like I. INTRODUCTION TO MATTER...

B R I C KS N OT ES |1 MODULE 1: GENERAL CHEMISTRY Main types: Lecture by John Mitchell L. Lua Þ SmecEc – soap-like/grease-like I. INTRODUCTION TO MATTER Þ NemaEc – thread-like Crystal System GENERAL CHEMISTRY Is a branch of science that deals with the study of maCer Crystal Systems in terms of its Crystal Substance Þ ComposiEon Cubic NaCl Þ Structure Tetragonal Urea Þ ProperEes Hexagonal Iodoform Þ Changes Rhombic Iodine Þ Energy Orthorhombic Ritonavir (II) Ma5er – is anything that occupies space and has mass. Monoclinic Sucrose, Ritonavir (I) Þ Mass – amount of maCer present in an object Triclinic Boric Acid Þ Volume – amount of space occupied by an object STATES OF MATTER Þ Weight – mass x gravity PROPERTIES OF MATTER INTENSIVE/INTRINSIC PROPERTY ProperEes that are independent on the amount of maCer  present Examples: Þ Density, specific gravity, boiling point, melEng point, organolepEc properEes EXTENSIVE/EXTRINSIC PROPERTY  ProperEes that are dependent on the amount of maCer present. LAWS OF MATTER LAW OF DEFINITE PROPORTION  Examples: Þ Mass, volume, heat content, pressure Also known as Proust’s Law/ Law of constant composi3on States that the composiEon of a pure compound is CHANGES OF MATTER always the same regardless of its source.  PHYSICAL CHANGE In pure compounds, the elements are always in the same Observed or measured without changing the idenEty of proporEon by mass The same raEo must be a whole number  maCer Change in phase of maCer Examples: LAW OF MULTIPLE PROPORTION Þ MP, BP, Solubility, Miscibility, Viscosity Also known as Dalton’s Law  Þ H20 (l) H20 (s) Atoms of two or more elements may combine in different raEons to produce more than 1 compound.  CHEMICAL CHANGE The mulEple raEos must be a whole number. Describe the change or reacEon a substance undergoes Change in both intrinsic and extrinsic properEes LAW OF CONSERVATION OF MASS Examples: No change is observed in the total mass of the substances Þ Flammability, FormaEon of Gas, FormaEon of involved in a chemical reacEon  Precipitate, ProducEon of Odor, Change in color. Þ Burning of paper II. CLASSIFICATION OF MATTER AND ITS PROPERTIES STATES OF MATTER STATES OF MATTER Proper?es Solid Liquid Gas Shape Definite Indefinite Indefinite Volume Definite Definite Indefinite IFA Strongest Strong Weakest MoEon VibraEon Gliding Random PURE SUBSTANCES Compression None Weak/None Strongest Elements: PLASMA Þ Simplest form of maCer that has definite chemical composiEons 4th state of maCer Þ Cannot be decomposed by simple Also known as mesophase/liquid crystals physical/chemical means into two or more ProperEes: different substances Þ Solid and flow-like properEes Þ Crystal la_ce – ordered arrangement of atoms  B R I C KS N OT ES |2 Compounds: directly proporEonal to the pressure of the gas Þ Composed of two or more elements that unite above the liquid chemically in different proporEons. Þ ⬆ pressure: ⬆ solubility of a gas Þ Cannot be changed into simpler substances Par?cle size under normal condiEons Þ ⬆ Solubility: ⬇ ParEcle size Presence of salts MIXTURES Þ SalEng-out: presence of salt decreases solubility. Substances that are not chemically combined Þ SalEng-in: presence of salt increases solubility. May be classified according to its: Þ Nature of parEcles: Homogenous vs TYPES OF SOLUTION Heterogenous Þ ParEcles size: SoluEon, Colloids, Suspensions TYPES DEFINITION Saturated soluEon SoluEon achieved the NATURE OF PARTICLES maximum solubility Unsaturated SoluEon Less solute than solvent Homogenous Heterogenous Supersaturated SoluEon More solute than solvent Consistent/uniform parts Physically disEnct parts; Has throughout; Has one many phases SOLUBILITY PRODUCT CONSTANT (KSP) phase Refers to the limit before saturaEon Examples: Examples: Þ Q < KSP: Unsaturated soluEon NaCl dissolved in water, Sand & Water mixture Þ Q = KSP: Saturated soluEon  Syrup, Alloys Þ Q > KSP: Supersaturated soluEon PARTICLE SIZES IV. ACID-BASE EQUILIBRIA AND BUFFER TRUE SOLUTIONS ACIDS Uniform mixture Composed of solute + solvent  Sour taste Litmus paper: Blue to red Atom, molecules, ions of the substance become Strong Acids: HCBNIPS dispersed Þ HCl Þ HBr  COLLOIDS Þ HNO3 Contains parEcles bigger than those in soluEons but Þ HI smaller than those in suspensions Þ HClO3  ParEcles of solute are broken down to the size of Þ H2SO4 molecules but are small enough and dispersed throughout BASES the medium BiCer taste  Property of colloids: Litmus paper: Red to blue Þ Tyndall effect – light scaCering effect Strong Bases: Þ Brownian Movement – zig-zag movement of Þ OH of Group I and Group II Elements parEcles  Þ AdsorpEon – capacity to adhere (sEck) to the SALTS  surface Formed from neutralizaEon reacEon Þ Charged electrically – zeta potenEal Types of salts: Þ Strong Acid + Strong Base = Neutral Salt SUSPENSIONS Þ Strong Acid + Weak Base = Acidic Salt Coarse mixture Þ Weak Acid + Strong Base = Basic Salt Finely divided solid materials distributed in liquid  Þ Weak Acid + Weak Base = No Salt III. SOLUTIONS THEORIES FACTORS AFFECTING SOLUBILITY Nature of solute & Solvent Theory Acids Bases Þ Solubility: refers to the maximum amount of Arrhenius Yields H+/H3O+ Yields OH- solute expressed in grams that can be dissolved Bronsted-Lowry Proton Donor Proton Acceptor in 100g of water Lewis Electron Acceptor Electron Donor Þ Miscibility: ability of one substance to mix with another substance IONIC EQUILIBRIA Temperature PH Þ ⬆ temperature: ⬆ solubility of a solid in a liquid Measured through Sorensen’s Scale Þ ⬆ temperature: ⬇ solubility of a gas in a liquid Þ pH = 7: Neutral Þ Exothermic: ⬆ temperature: ⬆ solubility Þ pH>7: Basic Þ Endothermic: ⬆ temperature: ⬇ solubility of a Þ pH 0: Non-spontaneous/Endergonic Þ G < 0: Spontaneous/Exergonic TRANSITION STATE THEORY  GIBBS FREE ENERGY SUMMARY TABLE Reactants will undergo a transiEon state in order to produce products #H #S T #G + + High - OTHER FACTORS  Low + ParEcle size - - Low - ConcentraEon High + Nature of reactant - + Any -  Temperature + - Any + Catalyst Þ Speeds up the reacEon or lowers acEvaEon  X. GAS LAWS energy FORMULA LIST Below is the list of formula for the different gas laws. CHEMICAL EQUILIBRIUM LE CHATELIER’S PRINCIPLE  If a stress is applied or placed on an equilibrium system,  the system will respond by altering the equilibrium in such a way as to minimize stress. FACTORS AFFECTING EQUILIBRIUM ConcentraEon  Þ Add A or B = forward reacEon Þ Add C or D = backward reacEon Pressure Þ ⬆ Pressure = ⬇ Volume = less no. of moles Þ ⬇ Pressure = ⬆ Volume = more no. of moles Temperature Þ Reactant – Endothermic Þ Product – Exothermic XI. NUCLEAR CHEMISTRY NUCLEAR CHANGE LAW OF MASS ACTION Change in structure, properEes, composiEon of the States that the rate of the reacEon Is proporEonal to the nucleus of an atom resulEng in the transformaEon of the product of the concentrate of the reactants to the power element into another element. of its coefficient in a balanced equaEon. Þ Nuclear Fission – spli_ng of heavy atom Þ Nuclear Fusion – union of 2 light atoms NUCLEAR CHEMISTRY UNITS Units of radioacEvity Þ Non-Si: Ci – 3.7 x 1010 decays/sec Þ SI: Bq – 1 decay/sec