Integrated Science 2 Quarter 2 LT Reviewer PDF

Integrated Science 2 QUARTER 2 LT REVIEWER  PART 1 Development of the Atomic Theory IS 2 LG 5.1: HISTORY OF THE DEVELOPMENT OF THE ATOM IS 2 Q2 PPT 1: DEVELOPMENT OF THE ATOMIC THEORY  Atoms and the Greeks An atom is the smallest entity that retains the identit...

Integrated Science 2 QUARTER 2 LT REVIEWER  PART 1 Development of the Atomic Theory IS 2 LG 5.1: HISTORY OF THE DEVELOPMENT OF THE ATOM IS 2 Q2 PPT 1: DEVELOPMENT OF THE ATOMIC THEORY  Atoms and the Greeks An atom is the smallest entity that retains the identity of an element (the simplest form of substance) The atom is a solid sphere that cannot be divided up into smaller particles or pieces. The idea of atoms started during the time of Democritus in 400 B.C. (Greek word "atomos" = uncuttable) BATCH 2029 INTEGRATED SCIENCE 2 - Q2  John Dalton's Atomic Theory (Laws) Law of Conservation of Mass - “The total mass of reactants before a chemical reaction is exactly equal to the products that result after the reaction is completed.” Law of Definite (or Constant) Proportions - "The proportion by mass of the elements in a given compound is always the same.” BATCH 2029 INTEGRATED SCIENCE 2 - Q2  John Dalton's Atomic Theory (Proven True) Elements made of indivisible and indestructible particles called atoms. An element like silver, consists of silver atoms. Silver atoms cannot be further split nor destroyed in order to form or create other atoms. This idea is supported by the Law of Conservation of Mass. Compounds are formed by the joining of the atoms of two or more elements. When an atom of an element is joined with another atom of another element, a compound is formed. Dalton further claimed that the ratio of the atoms combining to form a compound is always in a whole number ratio. A water molecule has one oxygen atom and two hydrogen atoms. Oxygen’s ratio to hydrogen is 1:2 (whole numbers). BATCH 2029 INTEGRATED SCIENCE 2 - Q2  John Dalton's Atomic Theory (Proven False) The atoms of a certain element are identical. This means that the properties and the appearance of one element are the same as every other atom of that same element. Example, an atom of sodium has the same mass and other properties as all the other sodium atoms. Different elements have different atoms. This means that chlorine atoms appear and behave differently from fluorine atoms. A major difference among atoms is their mass. An atom of a given element will always have a different mass from another element. BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Joseph John (J.J.) Thomson An English physicist that conducted experiments on cathode ray tubes The one who determined deflection of the cathode ray when exposed to an external magnetic field He discovered electrons through his research on cathode rays BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Thomson's Cathode Ray Experiment (1897) BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Thomson's Cathode Ray Experiment (1897) The cathode ray tube is made of glass from which most of the air has been sucked out. The negatively charged part (cathode) releases an invisible ray as electricity is transmitted through it. The cathode ray is attracted to the positively charged portion of the tube (anode). Since the cathode ray is invisible, a coating on the glass or the tube causes it to produce a bright light BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Observations Cathode rays move toward the positive plate and are deflected away from the negative plate. Thomson tried to observe cathode rays produced from different cathodes. Same set of particles and behavior were observed. These particles then could be a component of all matter. This discovery led to the conceptualization of the electron – negatively charged particles. BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Thomson's Plum Pudding Model (1904) From a spherical model, ideas on atomic model shifted to a plum pudding model The larger sphere is the atom. The smaller spheres embedded on the larger sphere represent the corpuscles (electrons) in this 'fluid'. BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Additional Inputs from Thomson He was able to calculate the charge to mass ratio of the electron. It is equal to 1.76 x 108 coulombs (C)/gram Note: Coulomb (C) is the SI unit for measuring charge. 1 C = 6.24 x 1018 electrons BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Robert Millikan American physicist and a professor at the University of Chicago Performed the famous oil drop experiment He was able to calculate the approximate mass of an electron using mass-charge ratio. BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Millikan’s Oil Drop Experiment (1909) BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Radioactivity Pioneers: Henri Becquerel, Pierre Curie, and Marie Curie Types of Rays: Alpha (positive); Beta (negative); Gamma (neutral) BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Ernest Rutherford A physicist from New Zealand who conducted experiments on alpha rays Considered as the "Father of Nuclear Physics" and a Nobel Prize recipient Famous for his Gold foil experiment BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Rutherford's Gold Foil Experiment (1910) BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Rutherford's Gold Foil Experiment (1910) Most of the alpha particles did not go scattering A few alpha rays were scattered (take note, alpha rays have positive charge) Some of the particles bounced from where they originated. BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Rutherford's Gold Foil Experiment (1910) Observations Conclusions Most of the α-rays went The majority of the atom is through the gold foil. mostly empty space. There must be a positively Some αlpha rays were charged particle within the deflected. atom which occupies a very small space. The αlpha particles that There was a much smaller bounced right back must be portion of the αlpha particles traveling directly into the core bouncing right back. that was positively charged. BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Rutherford's Nuclear Model (1911) The atom was like a small solar system where electrons are orbiting the positively charged nucleus. BATCH 2029 INTEGRATED SCIENCE 2 - Q2  The Quantum Theory By the beginning of the 20th century, the wave model of light was just about universally accepted by scientists. BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Max Planck Predicted accurately how the spectrum of radiation emitted by an object changes with its temperature Any energy emitted or absorbed by an object is restricted to pieces of particular sizes (quantum) Energies absorbed or emitted by atoms are quantized. Discovered the Planck Constant, a proportionality between frequency (v) and energy BATCH 2029 INTEGRATED SCIENCE 2 - Q2  The Planck Constant (1900) and Flame Test BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Albert Einstein Saw the idea of Planck in a new way of thinking about light Known for discovering the photoelectric effect Recipient of Nobel Prize for Physics BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Photoelectric Effect (1905) Electrons are ejected from the surface of a metal when light shines on the metal For each metal, a minimum frequency of light is needed to release electrons BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Line Spectra A spectrum that contains only certain colors or wavelengths Also known as the atomic emission spectrum Atomic fingerprint BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Neils Bohr Agreed with Rutherford's model of the atom, but also knew that it had a few problem Attended the lecture of Rutherford (1911) Planck’s theory + Rutherford’s planetary model BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Bohr’s Solar System Model (1913) Emission from H atoms was restricted to certain frequencies because the lone electron can possess only certain energies, each of which corresponds to a particular orbit around the nucleus Postulates: Allowed orbits and Quantum leaps BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Louis de Broglie A graduate student in France (Ph.D.) Wrote the shortest dissertation in history (3 pages long) Used Einstein’s famous mass-energy relationship equation (E = mc2) to explain matter waves. BATCH 2029 INTEGRATED SCIENCE 2 - Q2  de Broglie's Equation (1924) The relationship applies to all objects in motion The larger the mass or velocity, the smaller the wavelength Both light and electrons behave as waves and particles (wave-particle duality) Energy is quantized. BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Erwin Schrodinger Austrian physicist Derived an equation that describes electrons as waves in three- dimensional space Described what are orbitals BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Schrodinger's Electron Cloud Model (1926) An orbital is a well-defined region of three-dimensional space that can be inhabited by an electron. Comes in different shapes Dense region of orbitals form the Electron Cloud Model, the model we use today. BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Evolution of Atomic Models BATCH 2029 INTEGRATED SCIENCE 2 - Q2  PART 2 Atomic Structure IS 2 LG 5.2.1: HISTORY OF THE ATOMIC STRUCTURE IS 2 LG 5.2.2: ATOMIC STRUCTURE IS 2 Q2 PPT 1: DEVELOPMENT OF THE ATOMIC THEORY  Three Subatomic Particles BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Atomic Number vs. Mass Number Atomic Number (Z) Mass Number (A) Denotes the number of Amount of neutrons and protons within an element's protons found in an atom’s nucleus nucleus Z is unique for each Roughly the same as the element total mass of protons and neutrons because electrons have so little mass that it is considered insignificant. BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Symbols A is Mass Number (proton + neutron) Z is Atomic Number (proton) The number of neutrons in an atom is the difference between the mass number and the atomic number (A-Z). BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Example 1 The atomic number (the number on the lower part) is 11, meaning there are 11 protons The element’s mass number (number on top) is 23, so this means that there are (23 -11= 12) 12 neutrons present. Since the number of protons is equal to the number of electrons in a neutral atom, there are also 11 electrons. BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Example 2 The atomic number (number on the lower part) is 17, and the atomic mass (number on the upper part) is 35, so there are (35-17=18) 18 neutrons and there are 17 protons and 17 electrons in the Chlorine atom. BATCH 2029 INTEGRATED SCIENCE 2 - Q2  What are Ions? A charged atom so it either becomes positively or negatively charged When an electron is lost, there are now more protons than electrons which makes it positively charged or a cation. This is represented by Na+ (for Sodium) Conversely, an atom’s gain of electrons would make the number of electrons more than the number of protons. This makes the atom negatively charged which makes it an anion. This is represented by Cl - (for Chlorine) BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Practice Problems Symbol S Al Dy O Cr Mg2+ N3- Al As Co2+ S2- P3- Ni2+ Mass 32 27 163 16 52 24 14 27 75 59 32 31 59 Number Proton 16 13 66 8 24 12 7 13 33 27 16 15 28 Electron 16 13 66 8 24 10 10 10 33 25 18 18 26 Neutron 16 14 97 8 28 12 7 14 42 32 16 16 31 BATCH 2029 INTEGRATED SCIENCE 2 - Q2  PART 3 Isotopes, Isotones, and Isobars IS 2 LG 5.3.1: ISOTOPES, ISOTONES, AND ISOBARS IS 2 LG 5.3.2: AVERAGE ATOMIC MASS AND ISOTOPIC ABUNDANCE IS 2 Q2 PPT 2: ISOTOPES, ISOTONES, AND ISOBARS  Isotopes Atoms of the same element have different atomic masses From the Greek words isos meaning same and topos meaning place Have similar chemical properties but may differ in some physical properties BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Isotones Atoms that have different atomic mass and atomic number but have the same number of neutrons BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Isobars Atoms with the same atomic mass but with different atomic numbers Derived from the Greek words isos meaning equal and barys meaning heavy BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Isotopes vs. Isotones vs. Isobars Same mass Same number Same number Same number number? of protons? of electrons? of neutrons? Isotopes No Yes Yes No Isotones No No No Yes Isobars Yes No No No BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Element’s Atomic Weight (Formula) BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Example 1 For the naturally occurring carbon isotopes in nature, about Carbon-12 with a mass of 12.0000 amu is around 98.89%. And Carbon-13 with a mass of 13.0034 amu exists in nature for about only about 1.11%. Use the given information to prove that the atomic mass of carbon is really equal to 12.011 amu. Take note that 99.89% and 1.11% expressed as decimals are 0.9889 and 0.0111, respectively. BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Example 1 (Solution) BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Example 2 In nature, Chlorine-35 with a mass of 34.97 amu exists, another isotope is the chlorine-37with a mass of 36.95 am. If there are 75.53% of the Cl-35 isotope in nature while 24.4% are the Cl-37 isotope, what will be the atomic mass for the chlorine element? BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Example 2 (Solution) BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Example 3 In nature the following stable boron isotopes exists: 510B (19.78%; 10.0129 amu) and 511B (80.22%;11.0093 amu. Use this to determine the average atomic mass of boron. = (0.1978)(10.0129 amu) + (0.8022)(11.093 amu) = 1.981 amu + 8.899 amu = 10.88 amu BATCH 2029 INTEGRATED SCIENCE 2 - Q2  PART 4 Properties and Changes in Matter IS 2 LG 6.1.1: PROPERTIES OF MATTER IS 2 LG 6.1.2: CHANGES IN MATTER IS 2 Q2 PPT 3: PROPERTIES AND CLASSIFICATION OF MATTER  Properties, what are they? These are observable unique characteristics of a substance that give its unique identity. Can be either Physical (Extensive or Intensive) or Chemical BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Physical vs. Chemical Properties Physical Properties Chemical Properties Properties that are directly Properties that are observed even without observed and described changing the identity of the when the substance has substance. undergone change in Dependent on weaker identity. intermolecular forces Dependent on stronger present between molecules intramolecular forces present between molecules BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Physical Properties (Examples) Property Example Temperature The temperature of water in the flask is 25°C. Structure Ice is crystalline. Glass is amorphous. Color Sulfur is yellow. Bromine is a reddish-brown gas. Taste Acids are sour. Bases are bitter. Odor Benzyl acetate smells like jasmine. Hydrogen sulfide smells like rotten eggs. Boiling point Water boils at 100 °C. Ethyl alcohol boils at 78.5°C. Freezing point Water freezes at 32 °F. Methane freezes at -182 °C. Hardness Diamond is exceptionally hard. Sodium metal is soft. Conductivity Metals conduct heat and electricity. Diamond is a poor conductor. Solubility Ethyl alcohol dissolves in water. Gasoline does not. Density Water has a density of 1 g/mL. The density of gold is 19.3 g/cm3. BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Chemical Properties (Example) Figure: Chemical reaction: Copper and nitric acid The dissolved copper produces the blue-green solution; the reddish-brown gas produced is nitrogen dioxide. BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Physical and Chemical Properties (Copper) Physical Properties Chemical Properties Malleable and ductile Slowly forms a blue-green Can be melted and mixed carbonate in moist air with zinc to form brass Reacts with nitric or sulfuric Reddish-brown and acid metallic luster Slowly forms a deep blue Melting point: 1083 °C solution in aqueous ammonia Boiling point: 2570 °C BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Extensive vs. Intensive Physical Properties Extensive Physical Properties Intensive Physical Properties Properties that depend on Properties that do not the quantity or amount of depend on the quantity or matter. amount of matter. Examples are mass, Reliable in describing the volume, area, length. identity of a substance. Ex: density, melting and boiling points, odor, color BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Extensive vs. Intensive Properties (Example) BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Physical vs. Chemical Changes Physical change happens when the Chemical change physical appearance such as shape, happens when new phase or volume of a substance is substances are changed without changing its formed after a chemical composition. chemical reaction. ▪ Condensation of water vapor to form clouds ▪ Burning of paper ▪ After leaving a mixture of sand and water for ▪ Water and salt are produced after the some time, water is separated from the reaction of mixture through decantation hydrochloric acid, an ▪ Iron filings are separated from sand using a acid, and sodium magnet hydroxide, a base ▪ Salt is retrieved from sea water after evaporation BATCH 2029 INTEGRATED SCIENCE 2 - Q2  PART 5 Classification of Matter IS 2 LG 6.2.1: CLASSIFICATION OF MATTER I IS 2 LG 6.2.2: CLASSIFICATION OF MATTER II IS 2 LG 6.2.3: CLASSIFICATION OF MATTER III IS 2 Q2 PPT 3: PROPERTIES AND CLASSIFICATION OF MATTER  Classification of Matter BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Pure Substances Matter that has definite or fixed composition. Can be an element or a compound Represented by a chemical formula Either elements or compounds BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Pure Substances (Elements) A pure substance composed on only one kind of atom Defined by its atomic number (number of protons in the nucleus) whether it is isolated or combined The simplest form of substance BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Elements (Metals) Usually solids at room Have high melting points temperature When they react with acids Have shiny or metallic luster to form hydrogen gas Can conduct heat and Metal oxides form bases electric current when dissolved in water Malleable and ductile Examples: Copper (Cu), Silver Usually sonorous (Ag), Gold (Au), Iron (Fe), Mercury (Hg), Gallium (Ga) Have high density BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Elements (Non-Metals) Usually solids or gases at Have low melting points with room temperature some exceptions Have dull luster Non-reactive to acids Poor conductors of heat Non-metallic oxides form and electricity acids when dissolved in water Brittle materials Examples: Phosphorus (P), Non-sonorous Sulfur (S), Neon (Ne), Argon (Ar), Krypton (Kr), Xenon (Xe) Have low density BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Elements (Metalloids) These elements share characteristics possessed by both metals and non-metals. In the periodic table, they are found along the zig-zag line. Commonly used as semiconductors BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Pure Substances (Compounds) A pure substance composed Components of a compound of two or more elements can be separated through chemically combined processes that entail high The elements come in fixed amount of energy proportions (Law of Definite Separation processes include Proportions) electrolysis, photolysis, and Components of a compound pyrolysis cannot be decomposed by ordinary physical means. BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Compounds (Examples) Water: H2O Table Sugar: C12H22O11 Baking Soda: NaHCO3 Table Salt: NaCl Household Bleach: NaHClO Milk of Magnesia: Mg(OH)2 BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Classification of Matter BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Mixtures Matter that has variable composition A blend of two or more pure substances Can be a combination of two or more compounds, or an element and a compound The physical properties of the constituents are retained in a mixture. BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Homogenous vs. Heterogenous Mixtures Homogenous Mixtures Heterogenous Mixtures Do not contain visibly Mixtures that have visibly different parts different parts. Also known as solutions Properties of the individual Composed of a dissolving substances remain distinct medium (solvent) and Include two groups: dissolved medium (solute) suspensions and colloids Solubility vs. miscibility BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Types of Solution Systems / Kinds of Mixtures System Example Gas - Gas Air in a scuba tank is primarily a mixture of nitrogen, oxygen, and argon gases. Gas - Liquid Oxygen and carbon dioxide are dissolved in seawater. Liquid - Gas Moist air exhaled by the scuba diver contains water droplets. Liquid - Liquid When it is raining, fresh water mixes with seawater. Solid - Liquid Solid salts are dissolved in sea water. Solid - Solid The air tank is made of an alloy – a mixture of two metals. Kind of Mixture Particle Size Characteristics Suspension >1000 nm Murky or opaque to light, separates on standing, filterable Often murky or opaque to light, doesn't separate on standing, Colloid 2.0-1000 nm nonfilterable Solution 0.2-2.0 nm Transparent to light, no separation on standing, nonfilterable BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Tyndall Effect The effect of light scattering in colloidal dispersion, while showing no light in a true solution Used to determine whether a mixture is a true solution or a colloid. BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Mixture Separation Technique (Filtration) Used to separate an insoluble solid component of a mixture by passing the mixture through a filter or membrane The size of the filter openings is smaller compared to the size of individual solid particles. BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Mixture Separation Technique (Decantation) Separation of a liquid component from solids that have settled BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Mixture Separation Technique (Evaporation) A method of recovering the solid component of a mixture by letting the liquid component evaporate by heating BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Mixture Separation Technique (Distillation) A way of separating a mixture of liquids on the basis of their boiling points As one component reaches its boiling point, it evaporates from the mixture and is allowed to cool and condense. BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Mixture Separation Technique (Flotation) A method of separating components of their mixture on the basis of difference in densities Air supply (not the band!) BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Mixture Separation Technique (Magnetism) A way of separating a mixture of metals and non-metals through a magnet. BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Mixture Separation Technique (Centrifugation) A method of separating components of a colloid by spinning the sample in a centrifuge. Separation is based on differences in densities. BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Mixture Separation Technique (Chromatography) Separates components of a mixture based on how quickly molecules dissolved in a mobile phase solvent move along a solid phase BATCH 2029 INTEGRATED SCIENCE 2 - Q2  PART 6 Acids, Bases, and Salts IS 2 LG 6.3.1: ACIDS, BASES, AND SALTS I IS 2 LG 6.3.1: ACIDS, BASES, AND SALTS II IS 2 Q2 PPT 4: ACIDS, BASES, AND SALTS  Properties of Acids Tends to form H+ ions when React with active metals to dissolved in water. form hydrogen gas. Most acid formulas start Taste sour (but not all acids with H as in H2CO3 are advised to be tasted). (carbonic acid), HCl Turn blue litmus paper to red, (hydrochloric acid), bromothymol blue to yellow. HC2H3O2 or CH3COOH Corrosive materials (acetic acid) Their pH value is less than 7 BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Properties of Bases They tend to form Not reactive to metals. hydroxide ions (OH-) when Taste bitter (but not all bases dissolved in water. are advised to be tasted). Most base formulas end Turn red litmus paper to blue. with OH as in Mg(OH)2 Bromothymol blue retains its color when added to a base. (magnesium hydroxide), Al(OH)3 (aluminum Feel slippery when in contact to the skin. hydroxide) and NaOH (sodium hydroxide). Their pH value is greater than 7 BATCH 2029 INTEGRATED SCIENCE 2 - Q2  pH Scale Developed by Swedish The pH scale is a 14-point scale. chemist Soren Sorensen The midpoint of the scale (7) is Represents the strength of designated for neutral pH (pure an acid or base based water). This value is based from on the concentration of the property of water to undergo autoionization. hydronium ions (H3O+) in a solution If pH < 7, the substance is acidic. If pH > 7, the substance Equation: pH = -log(H O ) 3 + is basic. BATCH 2029 INTEGRATED SCIENCE 2 - Q2  pH Scale BATCH 2029 INTEGRATED SCIENCE 2 - Q2  pOH Scale Counterpart of the pH scale Represents the concentration of hydroxide ions in a solution as shown in the equation: pOH = -log[OH-] It is also a logarithmic 14-point scale If pOH < 7, the substance is basic. If pOH > 7, the substance is acidic. BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Neutralization Refers to the reaction between an acid and a base. The end products would be salt and water. A salt is any compound made up of a metallic ion (cation) and a non-metallic ion (anion). Example: HCl(aq) + NaOH(aq) --> NaCl + H2O BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Indicators These are substances that change color when added to an acid or a base. Colors can indicate if a substance is an acid or a base. Indicator Color if acid Color if base Red litmus paper Red (no change) Blue Blue litmus paper Red Blue (no change) Bromothymol blue Yellow to Green Blue (no change) Phenolphthalein Colorless Pink to Purple Methyl red Red Yellow Red cabbage decoction Red Green BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Indicators BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Indicators BATCH 2029 INTEGRATED SCIENCE 2 - Q2  PART 7 Forces IS 2 LG 7.1.1: FORCES I IS 2 LG 7.1.2: FORCES II IS 2 LG 7.1.3: FORCES III IS 2 Q2 PPT 5: FORCES  Force Force is a push or a pull Has an SI unit of newtons (N) Force is a vector quantity ▪ Vector quantities have both magnitude (measurement) and direction ▪ The direction may be specified in terms of the vector’s orientation on the x-y plane, where the x-axis is along the horizontal and the y-axis is along the vertical. ▪ The direction may also be specified in terms of cardinal directions North, South, East, and West. BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Force Force can make an object move Force can stop an object from moving Force can change an object’s shape or the direction of the object’s motion. CONTACT FORCE act when two objects interact with each other through direct physical contact. ACTION-AT-A-DISTANCE FORCE are interactions between two interacting objects that are not in direct contact with each other but can employ a push or pull in spite of distance. BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Contact Force (Normal Force) The force exerted from the surface where a body lies or rests It is perpendicular with the surface. BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Contact Force (Applied Force) An interaction of one object by a person or another object to accelerate, change velocity, or change the direction of another object BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Contact Force (Tension) Forces that are directed toward ropes, cables, and strings BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Contact Force (Spring Force) The spring force occurs when a spring compresses or extends. The direction of this force is always contrary to the direction of the displacement or size of deformation. Hooke’s law: F = -kx BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Contact Force (Air Resistance) The type of force the air exerts on a moving object This force is opposite to the movement of a falling object. This force is stronger for objects with high speed and larger surface area. BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Contact Force (Friction) When two objects are sliding against one another, a force of friction acts Force parallel to the surface It is always opposite to the direction of motion. BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Contact Force (Friction) The ratio of frictional force, f, over the normal force, FN, is equal to the frictional coefficient, μ, and is given by: μ = f FN fk = μkFN and fs = μsFN BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Action-At-A-Distance Forces (Gravitational Force) Gravity is a natural phenomenon by which a planet or other bodies draw objects toward the center. The gravitational force that the Earth exerts on the object is described as the weight of an object. Weight is calculated by multiplying mass and acceleration of gravity, w = mg. The weight always acts downward, toward the center of the Earth. BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Action-At-A-Distance Forces (Gravitational Force) Gravity is therefore affected by the mass of the object. Gravitational force is greater when the object has a greater mass. The Sun has such a large mass that its gravitational force attracts all other objects in the solar system and keeps orbiting around it. BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Action-At-A-Distance Forces (Magnetic Force) Magnetic force is commonly defined as the attractive or repulsive force applied between electrically charged moving particles. Magnetic forces are strongest when the magnets are touching but they have the ability to exert push at a distance. BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Action-At-A-Distance Forces (Electric Force) Exerted between any two charged objects. Electrical force is collinear with the electric field. Two objects with similar charges (positive and negative) will push away from one another (repel). Objects with opposite charges (one positive and one negative, will pull toward each other (attract). BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Free-Body Diagrams (FBDs) Free-body diagrams are graphical representations of vectors, such as forces, to illustrate the forces acting on an object Tips on drawing FBDs: ▪ Is it on Earth? If yes, then there is weight and it is straight down ▪ Is it on a surface? If yes, then there is a normal force and it is perpendicular to the surface ▪ Is there a rope involved? If yes, then there is tension and it acts along the rope ▪ Is it on a rough surface? If yes, then there is friction and it is parallel to the surface opposite the motion or intended motion ▪ Is someone pushing or pulling the object? If yes, then there is an applied force and it is in the direction indicated BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Free-Body Diagrams (FBDs) Examples 4 N book resting atop a table An 8 N book on top of a table slides after being horizontally pushed by a 14 N force to the right. The kinetic frictional coefficient, μk , between the book and the table is 0.3. BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Free-Body Diagrams (FBDs) Activity A block is suspended from a massless rope. A sled is pulled along a smooth (frictionless) horizontal patch of ice by an applied force directed at 30° above the horizontal. A box is being pushed up a rough incline. A wagon is pulled along the floor at an angle of 20° above the horizontal. Ignore frictional effects. A gymnast holding onto a bar is suspended motionless in mid- air. The bar is supported by two ropes that attach to the ceiling. BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Free-Body Diagrams (FBDs) Activity A book is being pushed against the wall. A college student rests a backpack on his shoulder. The pack is suspended motionless by one strap from one shoulder. A skydiver is descending with an increasing downward velocity. Consider air resistance. A car is coasting to the right and slowing down. Neglect air resistance A force is applied to the right to drag a sled across loosely packed snow with a rightward acceleration. Neglect air resistance. BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Net Force (Fnet) or Summation of Forces (∑F) The total or sum of forces exerted on an object The object will move or change the direction of its motion on the direction of the summation of forces acting or exerted on it. ∑F = √ ∑Fx2 + ∑Fy2 where ∑Fx is the horizontal summation of forces or the total of all forces lying horizontally or on x- axis; and ∑Fy is the vertical summation of forces or the total of all forces lying vertically or in the y-axis BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Finding the Direction of Net Force ∑Fx ∑Fy ∑F direction + 0 +x-axis or East - 0 -x-axis or West 0 + +y-axis or North 0 - -y-axis or South + + Quadrant 1 or Northeast + - Quadrant 4 or Southeast - + Quadrant 2 or Northwest - - Quadrant 3 or Southwest BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Finding the Net Force (Fnet) Examples The following forces were exerted on a box. Use a cardinal plane to create the free-body diagram of the box and find the magnitude and direction of the net force acting on it. F1 = 5 N South, F2 = 7 N North, F3 = 8 N West, F4 = 4 N East. The following forces were exerted on a box. Find the magnitude and direction of the net force acting on it. F1 = 10 N South, F2 = 7 N North, F3 = 2 N West, F4 = 5 N East. BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Finding the Net Force (Fnet) Examples A 14 N of force attempts to push a 6 N plastic box atop a table to the right but fails. If the ∑Fx and ∑Fy acting on the plastic box are both equal to zero. Find the static frictional coefficient between the plastic box and the table. (Hint: Use the ∑Fy, to solve for the normal force, F N, and use the formula below to define the static frictional force. fs = μsFN) BATCH 2029 INTEGRATED SCIENCE 2 - Q2  PART 8 Newton's Laws of Motion IS 2 LG 7.2.1: NEWTON'S LAWS OF MOTION I IS 2 LG 7.2.2: NEWTON'S LAWS OF MOTION II IS 2 LG 7.2.3: NEWTON'S LAWS OF MOTION III IS 2 LG 7.2.4: NEWTON'S LAWS OF MOTION IV IS 2 Q2 PPT 6: NEWTON'S LAWS OF MOTION  Aristotelian View on Motion Natural Motion Violent Motion Proceeds from the nature Produced by pushes or pulls of an object It is imposed motion Motion depends on the Externally caused particular combination of Heavier objects fall faster elements an object than lighter ones. contains BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Galilean View on Motion (Galileo's Balls) BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Newton’s First Law of Motion Also known as the Law of Inertia Every body perseveres in its state of rest or of uniform motion in a right line, unless it is compelled to change that state by forces impressed thereon (direct translation). Every object continues in its state of rest or uniform velocity in a straight line, while no net force acts on it (Version 2.0). Validated Galileo’s claim: Force is not required to keep an object moving. BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Newton’s Second Law of Motion Also known as the Law of Acceleration The alteration of motion is ever proportional to the motive force impressed; and is made in the direction of the right line in which that force is impressed (direct translation). The acceleration of an object is directly proportional to the net force acting on it, and inversely proportional to its mass. The direction of the acceleration is in the direction of the net force acting on the object. BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Newton’s Second Law of Motion Describes the relationship among net force (Fnet) acting on a body, mass (m), and acceleration (a). Acceleration is defined as the velocity's rate of change of an object over a period of time: a = (vf – vi)/t; where vf is the final velocity, vi is the initial velocity, t is time elapsed. Fnet = ma; where greater net force results to greater acceleration (at constant mass) while greater mass results to less acceleration (at constant net force) BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Newton’s Second Law of Motion Consistency of units are important. BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Newton’s Second Law of Motion (Examples) A single force of 40.0 N acts upon a 5.0-kg block. What is the magnitude of the acceleration of the block? 8.0 m/s2 A heavy ball with a mass of 2.5 kg is observed to accelerate at a rate of 8.0 m/s2. What is the magnitude of the net force acting on this ball? 2.0 x 101 N A 3.0-kg block is being pulled across a table by a horizontal force of 80.0 N also experiences a frictional force of 5.0 N. What is the acceleration of the block? 25 m/s2 BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Newton’s Second Law of Motion (Exercises) A rightward force of 302 N is applied to a 28.6-kg crate to accelerate it across the floor. The coefficient of friction between the crate and the floor is 0.750. Determine the acceleration of the crate. A baseball star exerts a force of 3225 N (average value) upon the gym floor in order to accelerate his 76.5-kg body upward. o (a) Determine the acceleration of the player. o (b) Determine the final speed of the player if the force endures for a time of 0.150 seconds. BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Newton’s Second Law of Motion (Exercises) An object has a mass of 300.0 g. o (a) What is its weight on Earth? o (b) What is its mass on the Moon? o (c) What will be its acceleration on the Moon when a 0.500 N net force acts on it? How large a force F is needed to pull out a 6.0-kg block with an acceleration of 1.50 m/s2 if the coefficient of friction at its surfaces is 0.40. BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Newton’s Second Law of Motion (Exercises) When a horizontal force of 4.5 N acts on a block on a resistance-free surface, it produces an acceleration of 2.5 m/s2. Suppose a second 4.0-kg block is dropped onto the first. What is the magnitude of the acceleration of the combination if the same force continue to act? Assume that the second block does not slide on the first block. BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Newton’s Third Law of Motion Also known as the Law of Interaction To every action, there is always opposed equal reaction: or the mutual actions of two bodies upon each other are always equal, and directed to contrary pairs. Whenever one object exerts a force on a second object, the second exerts an equal force in the opposite direction. These action and reaction forces are equal in magnitude but opposite directions. They don’t act on the same body. BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Newton’s Third Law of Motion Identify the system. Determine the objects that will interact. Call them A and B. Take note: FAB = -FBA These forces do not act on the same object. Force A acts on B. Force B acts on A. Example: While driving down the road, a firefly strikes the windshield of a bus and makes an obvious mess in front of the face of the driver. Which of the two forces is greater: the force on the firefly or the force on the bus? BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Newton’s Third Law of Motion (Examples) Action Action Force Reaction Force The person pushes the water The water pushes the boat In Boat Paddling backward with a paddle. forward. The swimmer pushes the The water pushes the In Swimming water backward with their swimmer forward. hands and feet. The car's wheels push The road pushes the car In Driving Cars backward on the road. forward. The missile expels gases The gases push the missile In Rockets downward with high force. upward. The ball exerts an equal The Earth's gravity pulls the In Ball Dropping upward gravitational force on ball downward. the Earth. The gunpowder explosion The bullet exerts an equal In Bullets pushes the bullet forward out and opposite force, causing of the gun barrel. the gun to recoil backward. BATCH 2029 INTEGRATED SCIENCE 2 - Q2  PART 9 Fluids IS 2 LG 8.1.1: PROPERTIES OF FLUIDS I IS 2 LG 8.1.2: PROPERTIES OF FLUIDS II IS 2 Q2 PPT 7: FLUIDS  What are Fluids? A fluid is a collection of molecules that are randomly arranged and held together by weak cohesive forces and by forces exerted by the walls of a container A fluid flows or continuously deforms under a shear force. Both liquids and gases are fluids BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Density and Specific Gravity The density is, the mass per unit volume and is denoted by the Greek letter rho (ρ). The formula for density is: ρ = mass (in kg) / volume (in m3) A substance 's specific gravity is its density divided by the standard reference material's density, typically selected to be water at 4°C. Specific gravity is the ratio between the densities of the substance and water at 4°C. It has no units. BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Density (Exercise) A ball is measured at 50 grams and 20 mL. Find its density. If the density of a 250.0 mL fluid is 0.8765 g/mL, find its mass. A solid rectangular box measures 4.0 cm in length, 5.0 cm in width and 6.0 cm in height. Find the box’s density if the mass of the box is 150 g. A block of aluminum is 15.0 mL in volume and has a density of 40.5 g. What is its density thereof? Express your final answer in its proper significant digits. BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Triple Beam Balance (TBB) An instrument used to precisely measure mass of an object. Typically have a reading error of ± 0.05 grams. It is named for the three weight-carrying beams. How to Measure Using TBB: ▪ On the top of the pan, place the object. ▪ Shift the rider one notch at a time on the heaviest beam before the pointer drops to zero. Shift the rider one notchback. ▪ Shift the rider one notch at a time on the next beam, before the pointer falls to zero again. Moving the rider one notchback. ▪ Slide along the front beam with the rider until the pointer ends at empty. The object's mass is equal to the sum of the three beam readings. BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Density of Solids If a Regular Solid: ▪ Mass of a substance is determined using a balance ▪ If the substance is a regularly shaped solid, its volume is calculated from the formula for its shape (V = length x width x height = l x w x h). If an Irregular Solid: ▪ Fill the graduated cylinder halfway with water. Take the reading. ▪ Record the volume as the initial reading Vi ▪ Slide the stone into the cylinder. Do not spill any of the water. Take the reading. ▪ Enter their volume as the final reading Vf ▪ Get the difference between the final and initial readings to find the volume BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Density of Liquids Get the mass of a 10-mL graduated cylinder that is clean and dry. Record your result. Measure 10-mL of water and then record the result. Weigh the graduated cylinder together with the liquid. Determine the mass of water using a balance such that you get the difference between the graduated cylinder’s mass with the mass of the water and mass of the graduated cylinder alone for you to be able to obtain the water’s mass. Solve the density of the liquid using the formula BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Pressure Pressure is a scalar quantity that measures the amount of force exerted per unit area. The formula for pressure is: P = Force (in N) / Area (in m 2). The standard unit for pressure is Pascals (Pa) Fluids also exert pressure BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Pressure (Exercise) Suppose you are standing directly behind someone who steps back and accidentally stomps on your foot with the heel of one shoe. Would you be better off if that person were (a) a large professional basketball player wearing sneakers (b) a petite woman wearing spike-heeled shoes? A box on the floor has a weight of 250 N. The box rest on 0.25 m2 of surface. Calculate the pressure under the box. A 60.-kg performer balances on a cane. The end of the cane in contact with the floor has an area of 0.92 cm2. Find the pressure exerted on the floor by the cane. BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Science Instruments Involving Pressure Mercury Barometer - When atmospheric pressure is higher, the mercury column is pushed taller. When lower, the height of the column of mercury drops. Sphygmomanometer - A device used to measure blood pressure, the measurement of force exerted by blood on the arterial walls. It measures both systolic and diastolic blood pressure. BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Systolic vs. Diastolic Blood Pressure Systolic blood pressure indicates how much pressure your blood is exerting against your artery walls when the heart beats. Diastolic blood pressure indicates how much pressure your blood is exerting against your artery walls while the heart is resting between beats. High: 140+/90+, Middle: (121-139)/(81-89), Normal: 120-/80- BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Fluid Pressure P = ρgh Pressure = (density)(gravitional constant)(height/depth) BATCH 2029 INTEGRATED SCIENCE 2 - Q2  Pressure (Exercise) A certain town receives its water directly from a water tower. If the water on the top of the tower is 26.0 m above the water faucet in a house, what should be the pressure at the faucet? The figure above shows aerial views from directly above two dams. Both dams are equally wide (the vertical dimension in the diagram) and equally high (into the page in the diagram). The dam on the left holds back a very large lake, while the dam on the right holds back a narrow river. Which dam has to be built stronger? BATCH 2029 INTEGRATED SCIENCE 2 - Q2  THE END INTEGRATED SCIENCE 2 QUARTER 2 LONG TEST REVIEWER