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LESSON 1.1 HISTORY common among them is the fact that they are composed of tiny particles. All kinds of matter are particulate in nature. These particles may be in the form of molecules, atoms, or ions. Atoms are the building blocks of matter. These particles are constantly moving and have a unique...

LESSON 1.1 HISTORY common among them is the fact that they are composed of tiny particles. All kinds of matter are particulate in nature. These particles may be in the form of molecules, atoms, or ions. Atoms are the building blocks of matter. These particles are constantly moving and have a unique arrangement in each state of matter. This lesson tackles the ancient views on matter and how the particulate nature of matter evolved. Towards the end of the discussion, a comparison of the arrangement, relative spacing, and motion of particles of solids, liquids, and gases are presented to justify their nature. Ancient Views on Matter Matter is anything that has mass and volume. But before this concept was established, ancient Greek philosophers were the first to speculate the nature of matter by providing different assumptions on what it is made of. Though Greek philosophers have ideas on what comprises matter, they only speculated on the nature of materials around them as they were not able to conduct experiments that will validate their assumptions. (?) How do ancient philosophers view matter? One thing that Greek philosophers have agreed upon is the idea that all materials are made up of one primal matter. However, they differ in terms of what this primal matter was. According to Thales of Miletus (625-547 BC), the basic composition of matter was water since this material is found almost everywhere. On the other hand, Anaximenes (585-525 BC) proposed that matter was made up of air since its existence is more fluid than water. However, Heraclitus (535-475 BC) opposed these ideas as he believed that matter was made up of fire, since this element is a good representation of a “changing world.” Another Greek philosopher, Empedocles (430-387 BC), combined the ideas of previous philosophers about the nature of matter. According to Empedocles, aside from water, air, and fire, matter was made up of earth too. This started the notion that matter was made up of four primal elements—water, air, fire, and earth. DX LV ¥ air fire water earth (TERRI The four elements that compose matter based on the views of Empedocles fire hot dry air earth wet cold water ees The four elements are a balance between two qualities. For example, fire is hot and dry, but earth is dry and cold. ‘i aes The four elements are a balance between two qualities. For example, fire is hot and dry, but earth is dry and cold, Aristotle (384-322 BC), a renowned and influential philosopher during his time, expounded the idea of Empedocles. He described each element as a balance between two qualities. This allows early Greeks to explain the transformation of primal matter. For instance, air, which is hot and wet, will be converted to fire when dried while maintaining heat. Aside from the idea that matter was made up of four elements, Aristotle suggested that all Space is filled up with matter, thus, implying that there are no empty spaces. Since matter is not void, this means that it is divisible and can be cut into pieces over and over again. This started the principle of continuity of matter, wherein matter can be broken down into pieces and as you do so, you will not be able to obtain its smallest parts. Since Aristotle was well respected during his time, his idea was accepted and held by many over a long time. Prior to Aristotle's assumptions about the nature of matter, Leucippus (500 BC) and his student Democritus (460-370 BC) thought that all materials are made up of tiny bits of matter which cannot be divided further. The tiny indivisible part that makes up a matter is known as atom, which came from the Greek word atomos which means indivisible. => ae cut | clay cut in half ©-® and again M man» etc. mm} © atom ARPS An illustration that depicts Democritus's view of matter. Matter can be cut into Several pieces but it cannot go on continuously since doing so will give the ultimate particle of matter—atom which is indivisible. + How does the idea of Democritus result in the formulation of the particulate nature of matter? Particulate Nature of Matter The idea of Democritus paved the way in establishing that matter is made up of particles instead of a primal material. This also started the principle of discontinuity of matter, wherein matter cannot be further divided into smaller bits once the ultimate particle of matter (atom) is obtained. There are four main ideas in the particulate nature of matter: 1. Matter is composed of discrete particles. 2. There is an empty space between particles of matter. 3. The particles of matter are in constant motion. 4. There are forces that act between the particles. Discrete Particles of Matter Matter is made up of distinct particles. These particles may be in the form of molecules, atoms, or ions. Atoms are the building blocks of matter. These are tiny indestructible particles that usually possess unique characteristics that define a certain matter. An atom is neutral by nature, but when it becomes charged—either positively or negatively—it becomes an ion. An ion is a particle or group of particles that are charged. A negatively charged ion is called anion while a positively charged ion is called cation. On the other hand, molecules are particles that are made up of two or more atoms that are chemically combined. On a macroscopic level, it is easy to describe what makes up a certain material. For instance, a table is made up of wood which is attached to one another using iron nails and/or wood glue. The surface of the wood is covered by either paint or varnish. However, distinguishable particles that make up a wood are hard to visualize on a macroscopic level. This prompted the use of particulate drawings to represent matter. Particulate drawings are illustrations used to have a visual representation of particles that make up matter, GRRE) A block of wood (left) can be easily observed as hard, and based on its internal composition, it is made up of compact particles (right). LESSON 1.2 NATURE OF PARTICLES ‘i Aes Particles that are close to one another (left) move in vibratory motion while particles that are far apart (right) move fast and in random directions. Temperature can affect the movement of particles in matter. With an increase in temperature, particles in matter gain kinetic energy. The higher the kinetic energy of the particles, the faster its movement. Thus, increasing the temperature of matter enables its particles to move swiftly as well. The diagram below shows an increase in the speed of moving particles as temperature increases. W = = | heat energy increases kinetic energy increases JESRFAAs the temperature increases, particles gain kinetic energy which results in their fast movement. Forces between Particles Particles in matter are held by forces. Intermolecular forces or forces that exist between particles may be attractive or repulsive. For instance, a water droplet is able to maintain its shape due to the attractive forces that exist between its particles. On the other hand, water droplets are seen sliding down outside the glass of a cold drink due to the repulsive force that exists between the water particles and glass particles. aes The formation of water droplets on the sides of a glass of cold drink shows the attractive and repulsive forces between particles of water. Compact materials show a strong attractive force between its particles. This is the reason why this kind of material is able to keep its shape and volume. On the other hand, almost negligible force exists between particles of matter that are far apart from one another. Understanding the basic principles of the particulate nature of matter can provide a better view of the microscopic level of solid, liquid, and gas. Fig. 1.8 shows the particulate drawings of solid, liquid, and gas. The arrangement of particles, its motion, and intermolecular forces dictate the kind of state in which matter exists. ® © © "© ve © a (S] © OX » JZ © © Arrangement of Particles Particles in a Solid matter are closely packed and are arranged in an orderly manner. This close arrangement limits the spaces between the particles of solid. Liquid particles are also close to one another but its arrangement is not as orderly as solids. However, there are relatively bigger spaces between liquid particles than solids. On the other hand, particles in the gaseous matter are far apart from one another and are arranged randomly. The far distances between particles make a gaseous matter mostly empty space. Intermolecular Forces The limited space between particles of solids is a consequence of the strong attractive forces between its particles. Particles in a solid matter are closely packed due to the strong attractive forces that hold them together. This is the reason why solids are able to maintain its shape and volume and have low compressibility and fluidity. The attractive forces between liquid particles are also strong but not as strong as the intermolecular forces in solids. This particulate nature allows most liquids to flow with ease and follow the shape of its container. However, attractive forces between gaseous particles are very minimal and almost negligible. Particles in gaseous matter tend to neglect one another due to the huge distances between them. Gases are highly compressible due to the very minimal forces that exist between its particles. key oil balloons RA A key is able to maintain its shape and volume due to the strong attractive forces between its molecules. Oil is able to flow with ease due to the moderate forces that hold its particles. The air inside the balloon may be compressed due to the very minimal forces existing between its particles. Motion of Particles Particles in all states of matter are in constant motion. However, the arrangement of particles in each state of matter also dictates its kind of movement. Solid particles exhibit vibratory motion but in a fixed position. The limited spaces between particles of solids also restrict its motion to back-and-forth movements in defined positions. The relatively bigger distances between liquid particles allow them to slide past one another. This is the reason why liquids tend to occupy the bottom part of a container, On the other hand, the huge Spaces and very minimal attractive forces between particles of gases enable them to move swiftly and in random directions. Energy of Particles Since particles are in constant motion, they also possess kinetic energy. The rate of motion of particles in matter also tells the amount of kinetic energy they possess. In solid matter, the particles are confined in fixed positions as they vibrate. The slow vibratory motion of solid particles shows that low energy they possess. Liquid particles have moderate speed as they slide past one another. This also results in the moderate energy that liquid particles possess. Moreover, gas particles that are moving swiftly and randomly possess high kinetic enerev. KEY POINTS LESSON 1.1 - 1.2 LESSON 1.3 GENERAL PROPERTIES OF MATTER General Properties of Matter The basic definition of matter is anything that has mass and occupies space. Given this description, mass and volume are properties that are common to all forms of matter. The characteristics of matter that are present in all kinds of matter are known as general properties of matter. When a property is observable only in a particular kind of matter, it is known as the specific property of matter. The fundamental properties that are used to describe matter are mass, volume, weight, density, and specific gravity. Mass Mass refers to the amount of matter in an object. This describes how much matter comprises a material. Matter is made up of discrete particles; thus, the amount of particles present in the material also measures its mass. The more matter is present in an object means the greater its mass. Mass is usually expressed in grams (g) or kilograms (kg). Materials that are compact have relatively greater mass than those with a hollow interior. For instance, a block of wood has a greater mass compared to a beach ball even though the latter one is greater in size. This is because a block of wood has more particles that are closely packed compared to a beach ball which has gas particles that are far apart from one another. Fig. 1.2.1. | A block of wood, though smaller in size, has a greater mass compared toa beach ball due to its compact composition. Weight Mass and weight are often interchangeable, but these are two different quantities. Since mass refers to the amount of matter in an object, it remains the same regardless of its location or the amount of gravity that acts on it. A materials composition does not change even if an outside force acts on it; thus, its mass remains unchanged. On the other hand, weight is the measure of force that acts on an object. It is expressed as the amount of matter (mass) multiplied by the gravitational force that acts on it. Thus, the greater the gravitational force that acts on an object, the “heavier” it weighs. In the same manner that a massive object has more weight. Since weight is a force, it is expressed in mewtons (N). In (EEE, the mass of an astronaut who travels to the moon is the same as his mass on earth. However, since the earth is about six times more massive than the moon, it has a greater gravitational force. This makes the astronauts weight on the moon only approximately one-sixth (1/6) of his weight on earth. DEF A comparison of astronaut’s mass and weight on earth and on the moon Volume The amount of space occupied by matter is known as volume. This property of matter can be measured using instruments with graduations or by getting the dimensions of the object and applying mathematical equations. For instance, the volume of liquids can be measured by a graduated cylinder. When the liquid is poured inside the cylinder, the graduation mark that the liquid reached is the measure of its volume. Volumes of liquids are often expressed in milliliters (mL) or liters (L). For solids with regular shapes, for example, a cube, its dimensions may be measured and multiplied by one another to get its volume. Volumes of solids are often expressed in cubic centimeters (cm®*) or cubic meters (m*). — => = ~~. - tength == a width aes Pouring a liquid in a graduated cylinder can measure its volume (left), while measuring and multiplying the dimensions of a cube will determine its volume (right). Density All matter has mass and volume. The relationship between mass and volume may be described by its density. Density is a physical property that expresses the ratio between mass and volume. Since density is a ratio between mass and volume, it is often expressed in kilograms per cubic meter (kg/m?) or grams per cubic centimeter (g/cm?). Density also tells how compact an object is. An object with greater mass has more compact particles than the lighter ones. Therefore, a massive object that occupies less space also possesses a higher density. On the other hand, a material is said to be less dense when it is lighter and occupies greater space. Table 1.2.2] shows the density of common substances. General Chemistry 1 ce, Technology, Engineering and Hathematice Unit 1: Matter feather aluminum pure gald stainless steel Specific Gravity Specific gravity is the ratic of a substances density to a standard substance. This is the reason why ft is also known as relative density. Water at 4°C, which is at its densest, is commanty used as a Standard for comparison of liquids and solids. On the other hand, air at room temperature (20°C) is the usual standard for comparizen of gases. However, the temperature and pressure of both samples and the reference must be specified toc te have an accurate comparizon. Since specific gravity is a ratio between two densities, it & a dimensionless quantity wherein no physical dimension is assigned. : a ' DIE. pycnometes, abso known as specific gravity bottle, is used to determine the density of liquids. 1.2 Properties of kalker Meking points of common metals arid alloys aluminum 660 brass 1699 cobalt 1495 carbon steel 1599 gold (pure} 1063 manganese bronze asd platinum 1176 stainless steel 1810 silver (pure) 961 Sterling Silver Go You Know? Tungsten i a metal with the highest melting point which is at S400°C This characteristic makes tungsten sumtable to use as bulb filaments. FEE. ight bulb with tungsten filament in theory, the melting paint of a solid matter is Similar to its freezing point as a liquid, For instance, the melting and freezing point of pure water at a standard condition i OC. However, for the case of fats and oil, the temperature at which they start to melt is higher compared to their freezing point. Fats and oils tend bo solidify faster at a lower temperature and take a higher temperature t melt. General Chemistry 1 chology. Engineering, and Mathematics Unit 1: Matter How can you distinguish physical from chemical properties of matter? Physical Properties of Matter Qualities that are readily observable or meazurable without changing the matters composition are known as physical properties. General properties such as mass, volume, weight, density, and specific gravity are all examples of physical properties. Physical properties are often used to describe or observe matter. For instance, to desconbe the physical appearance of matter, one may take note af how big ar small it is (Size), how t feels (texture), or how it appears (Shape/formveolor), Qualities such as size, texture, shape, and cofor are all physical properties of matter. Other examples of physical properties are melting point, boiling point, freezing paint, solubility, and metallic properties. Melting Point Solids have a tendency to tum inte liquids when 5ubjecied to heat. As solids absorb heat energy, its temperature increases, causing its particles to mave faster and dissociate from ane anather, This dissociation leads ic a phase change known as melting The temperature at which a solid matier changes to liquidis known as the melting point. The melting point of a material varies according to its composition. Materials that are compact and dense have higher melting points compared to lighter ones. Less compact materials have lower melting points. Some solids like metals are also capable of abserbing heat without meking fast. These materials are often used as components for electrical appliances. [EPICS eS) summarizes the melting point of commen metals and alloys. Freezing Point Liquids have a tendency to Solidify when cooled. When a liquid is cooled, its particles slow down as they lose kinetic energy due to a lower temperature. The slow mavement of particles allows them to clump together and form a solidi state. The temperature at which a Iiguid turns into a solid matter is knawn as the freezing point. 1.2 Propurties of batter Boiling Point When a liquid is heated, its particles absorb the heat energy. The gain in kinetic energy of particles allows them to break away from one another and move faster in random directions. This results in vaporization or the change from a liquid state to a gaseous state Qwapor) A heated liquid reaches a certain temperature at which its wapor pressure is equal to the pressure of its surrounding quid. This & known 25 the boiling point or the temperature at which liquid vaporizes. (EA The formation of bubbles in a heated liquid indicates that it is starting to bail. The boiling paint of liquids varies depending on the pressure of its surroundings. A liquid that is heated in a condition wath lower atmospheric pressure boils faster compared to a Giquid that is heated in a condition with normal atmospheric pressure. For instance, the boding point of water at sea bevel is 100°C. Take note that the altitude of a certain location affects its atmospheric pressure. The higher the akitude, the lesser the atmospheric pressune is. Thus, it will only take 89.4 for water to boil at an altitude of 6250) feet. Solubility When matenals are combined together, some of their components mix well while others da net. Materials that mix well form a homogeneous phase wherein the substance in a lesser amaunt {solute} dissolves in another substance of greater amount (solvent). The ability of a solute to dissolve in a given solvent is known as solubility. Though the zobubility of a substance varies depending on its composition, it is still considered as a physical property 25 one can tell whether a material & soluble ar nat by merely chserving its physical appearance. Different terms are used to desonibe the solubility of a certain material. A material is said to be highty soluble if it dissolves easily in a solvent. For the case of fluids lie lquics arid gases, substances are sad to be miscible if they mix well together. Some substances that do not completely miare said to be partially soluble or partially miscible. On the other hand, a material that does nat dissolve at all in a given sohvent is known to be insobulbbe or immiscible. ml ; —— [NES spoonful of sugar & soluble in water (left), however, Stirring it thoroughly will increase its rate of solubility. On the ether hand, the metal spoon & insoluble in water as it does nat dissolve while being used te stir the sclution fright}. Conductivity, Malleability, and Ductility Metallic properties are qualities that are observed specifically in metals. These properties set metals apart from ather material. Some metallic properties are conductivity, malleability, and ductility. The ability af a material to allow heat or electric charges to pass through easily & known as conductivity. Aluminum & often ved as a base material for cooking pats and pars due ta its high thermal conductivety. On the other hand, electrical wires are usually made up of copper as it conducts electricity fast. aluminum pots copper wires GED) Metals are good thermal and electrical conductors. Metal can be flattened into thin sheets due io its malleability. Aside from mabeability, metal can be eazhy drawn into wires due io its ductility. This property makes metal a good material for electrical wirings and components. GEE Gold is a good material for crafting jewelry due to its malleabiliny and ductiley. Chemical Properties of Matter The characteristics that can only be seen when the chemical idertity of a material & altered are known 2s chemical properties. These properties only become evident when a material undergoes a chemical change. The chemical properties of a certain material highly depend on its composition Some examples of chemical properties are biodegradability, combustibility, flammability, and reactivity. HSiodegradability The capacity of a material to decompose through the actions of microorganesms is known as biodegradability. The property may only be observed when a material undergoes decampositian. Organic: materials or carbon-based materials that usually come from living organzrs are said to have a higher biodegradabilty compared to the synthetic ones. summarizes the approaimate time for common materials to decompose in marine and tenrestrial environments. LED es Approwimate time for common maberiaks to OSCompaze im marine and ferret ermvronmenits Time to Decompose Materials Marine Environment Terrestrial Environment paper towel 2to.4 weeks lito 2 weeks apple core 2 months 4 ito 4 weeks tin cans £9 to 100 years aluminum cans 200 years SU to 100 years plastic bags £0909 years to forever Flammability and Combustibility The terms “flammable” and *combustible* are often used to desonibe the ability of a material to burn. (hese properbes may ony be obServed when maternal are subyected to combustion ar a chemical reaction between a substance (fuel) and oxygen which nesults in the generation of heat and light in the form of flame. However, the main difference between ine twp properties & the ease ard rate of how an obgect OUTS Combustibility refers to the ability of a material to combust or burn. When a material & exposed to a proper amount of heat, which is enough for it to ignite and react with axygen n the atmosphere, combustion happens. The combustibility of a certain material depends an its compensation. Highly wolatle materials or materials that eazby evaporate or sublime are often highly combustible On the other hand, flammability = the abdity of a combustible material to catch flame easily. However, it is important to nate that not all combustible materials are flammable. For instance, a block of wood may only burn when eqposed in a specific amount of heat and oxygen, but putting a flame near it wall not necessarily make it burn insarithy. eae Inc to oa matchstick = ue 5% Mane Up of a flammabt 2 COMpPBOLUNd WET conzer of zutur and phorus. This alogs the matcreabck to eas ly iene and Dum. LESSON 1.4 Lesson 1.3 Pure Substances and Mixtures [Nj Introduction Have you been is a buffet? It & a system of serving meals in the restaurant wherein different wards are placed on the table, and diners serve themselves. Like 2 buffet, the world offers variety in terms of materials that can be encountered. Some materials like racks, word, and water are visible while air is not. Some materials are pure in terms of their composition, while other materials are combinations of tao or more substances. There is so much diversity of materials in the environment, forcing scentists to classify matter into different groups. In this lesson, you will learn the different classification of matter. Matter may be classified according to its composition. Materials with a fixed composition are known as pure substances, while thase with varying composttions are known as mixtures. Pure sSubstances may be further classified as elements and compounds, while mixtures may be grouped as homogeneous or heterogeneous. Each group of matter has its unique properties that allow them to be detnguehable from other kinds of material. Matter may be classified according to their state or phase. The three States of matter are solid. liquid, and gas. Solid materials are rgd and have a definite Shape. Liquids, on the other hard, have a definite volume but mo definite shape. Uris solids, quads bend by follow the shape of is container and are able to flow with ease. Lastly, pases have no definite shape and wolume. Gases are often invsible but are highly compressible compared to solids. ard liquids. A = Be Be % iJ 4 = $i coins Equids in flasks zz emitted in factories WAKER] Matter can be grouped into Solids, liquids, or gases. Matter may be classified according to their properties. Properties are characteristics that a certain material possesses which makes it unique. Wateriabs may possess physical properties or characteritics that are observable even without changing the compositien of matter. Thus, matter may be dassfied according to their color, mass, volume, denaty, ard other physical characteristics. On the other hand, matter ako possesses. characterigtics that can only be observed once a material undergoes a chemical reaction. These properties are imown as chemical properties Materials around may be grouped according to their flammability, reactivaty, and biodegradability. flowers grouped according dolls arranged by size blocks of wood of differem to color Shapes Geer’ Materials may be classified according to color, size, and shape which are known as physical properties frum peelings as biodegradable GEES Materials may be dlacsified according to their bicdegradability which is a chemical property. planics. as nonbiodegradables Matter may be classified according to their composition. All matter = composed of tiny parteles called atoms. However, the compositan of atoms in a matter vanes. Substances have a fixed or definite composition. This kind af matter is made up af a specific number of atoms or groups of atoms that are combined through a chemical reaction. Mixtures, on the ather hand, are combinations of pao or mare substances. © What are pure substances and mixtures? Pure Substances & pure substance is a kind of matter with a definite or freed composition. Nabe that all materials are composed of atams. Thus, pure substances are made up af atoms, toa. However, they can be composed of a specific type of atom or combination of atoms. This compostion is fixed for this kind of matter. & pure substance also has definite physical and chemical properties such as appearance, melting point, and reactivity. Regardless of the amount of pure substance, it will always have the same properties because it is made wp of ane type of particle An element cannot be decomposed into simpler substances by physical ar chemical means. Thus, it is not possible to alter the identity of a certain element through ordinary chemical reactions. Physical changes such as melting, freezing, or cutting do not change the identity of pure substances. Take, for example, the case of gold, a metallic element that & often used for jewelry. Gold & malleable and has a low melting point, which makes ita Suitable material for jewelry making, Heating a sheet af gold to shape it into a ring wall not change it into anather sustance. It is still gald but with different shapes and sees. EET Gold is a metallic element that & commonly used for making jewelry. Snce elements are the simplest forms of substance, they are also considered as the building blocks of matter. This is because when elements react with one another, a new Subtarce in the form of a compound is formed. water HO (GRIER Water (Hol) is formed when two atoms of hydrogen (H) combined with one atom of axygen'[O). Pure zubatarces are classified inte cements and compounds. An clement is mads up of ane kind of atom, or two ar more of the same kind of atoms that are chemically combined. On the other hand, a compound is made up of different kinds of atoms that are combined thrawgh a chemical reaction. Compounds have different properties from the elements that make them up. s» te LE [a)ators of an element (6) molecules of an element (ec) molecules of a compound FESEFI an element is composed of only ane type of atom while a compound is composed of to or more different kinds of atoms that are chemically combined. Elements Elements are the semplest substances because they are made up of only one kind of atem. i & a pure substance that is composed of anky one type of atom. The atoms of one element are different from those of another element. For example, the element copper is composed only of copper atoms, while the element iron & composed anky of iron atoms. Elements of different lands ako differ in the atoms that make them up. There are 118 elements known to exdst in which 34 af these occur naturally on Earth, while the remaining 24 are synthetic. Each element has a place in an arrangement called the periodic table of elements. Each element has its own chemical name and symbol & chemical symbol converts of one to three letters. The first letter is always capitalized, and the other letters are always set in lowercase. The first letter is usually the first letter of the cement name, while the second letter is usually the Second letter of the element name. For instance, the chemical Symbol for Oxygen & DO, while the chemical symbol for Cakium is Ca. Some chemical symbols are taken from the Latin names of the given element. [EERE Shows a list of the elements and their Symbols from their Latin names. (EERE List of elements and their symbols from their Latin names. Symbol Latin name tin Sn stonnen tungsten W wolfrom A periodic table is a useful tool that can help in identifying elements that exhibit samilar properties. The table cdascfies the element into three general categories: metals, nonmetals, and metalloids. 12 34 5 6 7 8 9 10 11 12 13 14 15 16 17 18 Period | 1 f The Periodic Table of Elements He 2 Be BMcnotm z | me WH: as = LLEREETIEIT FF s WW #7 vw 7 8B Fd As Ed lin BY BY HR xe = Mo |) Hit Ta Wi ee Gs ir Pe As ag Gi (BH BO) cr > (Bae OBE GR Ee ah AS rae OS me en Wh A ate Ly Ts Ox Be Th Pa nip Bi Am cim ic Cts Fim ni io Ur GIG The periodic table of elements is the arrangement of all known elements according to theirchemical properties. (Metals: start at the left and make up most of the elements in the periodic table. In fact, all cements to the left of the staircase-lie line im the periodic table (except hydrogen) are generally dassified as meta. Nonmetals are at the right part of the periadic table and are aften shaded with different colors to distinguish them from metals. The metalloids lie between the metals and nonmetals. These elements form the staircaselike line in the periodic table. Metals have properties that distinguesh them from nonmetals. For instance, metals [except mercury) are solid at roam temperature. Metals have luster or the property that makes them shiny. Most metals exhibit malleability or a property that enables metals to be hammered inte thin sheets without breaking. Metals ako possess ductility or the ability to be drawn into wires. Also, metals are good conductors of heat and electricity. This & the meason why metal are good raw materials for making cooking pans, pots, and electrical wiring. hard disk speaker cassette tape ERE Examples of materials that utilize magnetic metals to function. Moametals, on the other hand, are the apposite of metals. Generally, nonmetals are either gaseous of dull solids. These elements are brittle as they break apart easy when subjected to a heavy blow. Monmetak. are poor conductors of heat and electricity. The major elements in eng things such as carbon, hydrogen, coygen, nitrogen, and sulfur are all nanmetals. Bromine & the only nonmetal that is liquid at room temperature. Metallaids jor zemimetals} are elements that exhibit properties of both metals and nonmetals. Some metallaids are shiny like metal but are also bretk bke a nonmetal. Metallaids can conduct heat and electricity but not as geod as how metals act as conductors. This is the reason why are known as Hlo=s Silver, platinum, and tungsten are examples of metals. nid You Know? Mercury & the only metal that is quid at roam temperature. It is a Shiny, silvery liquid metal that forms beads due to its high surface tendon. Mercury is als known as quicksilver due to its appearance ard mobility. FLEET Mercury has a high surface tension that enables it to form beads when Separated. Some metals ike iron, nickel, and cobalt possess magnetic properties. These magnetic materials are used in electric motors, generators and transformers, and storage devices Such as tape recorders and hard dicks. I Silicon and germanium are metallcads that are widely used in the manufacture of computer chips. How can elements be broken down into much simpler forms? Compounds Compounds are pure substances that are composed of two or more different elements that are combined in a fixed ratio bya chemical reaction. Many compounds are farmed naturally due is gealogic processes on Earth, while Some compounds are formed when an element reacts with ane of the gaseous elements in the air. Some compounds are products of chemical reactions between two or more compounds. Living things, like plants, produce glucose, an organk compound, during photasynthesss. [EEE curing phatorynthests, carbon choaige [CO,] reacts with water fixed mass ratio. Recall that water has hydragen and 1,0) and sunlight which yields glucaze ICH, The elements that comprise a compound exist in a arygen. Each molecule of water has twa atoms of hydrogen and one atom of oxygen. The three atoms are tightly held by a strong, attractive farce. The chemical bonds that hold atoms together in a compound cannot be broken easily. However, unlike elements, compounds can be broken down into simpler forms by means of a chemical reaction. For instance, when an electric current is passed through water, a chemical change takes place. The atoms of water molecules break apart into two elements « hydrogen and copper. Cathode 2H,0 — 2H, + ©, D in water electrolysis, an electric current is passed through water to separate its companents to oxygen and hydrogen. When elements combine to form compounds, their identities change as well. A chemical change akers the identity of the substance. The properties of elements that make up a compound are different from the properties of the compound formed. For instance, table salt has a chemical name sodsum chloride (Natl) as it is composed of one atom of sodium and one atom of chicrine. Table sak is often used as a food additive, but sodium alone is explosive, while chlorine can be toxic. Thus, this Shows that the chemical reaction between sodium and chlorine, both highly reactive elements, can produce acompound that is edible. © How do compounds differ from elements? Mixtures Mixtures consist of two or more substances that are combined physically. When two or more substances are put together, they form a mixture if there is no chemical reaction that took place between them. For example, water and table salt are both compounds. When table salt is dissolved in water, a brine or salt solution ts formed. The water and salt retain their properties even though they are mosed together. The brine tastes salty because of the presence of salt, but it also remains clear due to the characteristic of water. ae aa = $85.5 OS : [EEE Seawater is a mocture of dissolved als and water. Unlike elements and compounds, mixtures are not pure substances. instead, mixtures contain more than one type of Substance. Each substance in a mixture has the same chemical make up it had before the mixture is formed. Also, mixtures do not have definite proportions. The amount of substances present in a mature varies depending on the number of combined substances. For example, a person who prefers to drink a strong coffee will add less sugar in it than a person who prefers to drink a sweeter ane. Because of this, mixtures do not have definite properties. The properties af mixtures depend on the substanceshat are present in it. I Table zalt or Sodium chloride is a compound formed when sodium and chicrine combined together through a chemical reaction. Compounds may be classified according to the specific elements that are present. Organic compounds are substances that contain the elements carbon and hydrogen. The term “organic” is often associated with the word natural as it was believed before that only living things can produce organic compounds However, scientists eventually discovered that arganic compounds could also be produced anificially in laborateries. Mest organic: compounds are present in the food that the body needs in order to thrive. These organic compounds are carbohydrates, proteins, lipids, and nucleic acids. Inorganic compounds are substances that do not have carborehydrogen bonds. Carbon diode, water, and table salt are all examples of inorganic compounds. BA The food that a person eats provides the organic compounds that the body needs in order to grow and survive. Mixtures may be further classified as homogeneous or heterogeneous. Each type of mixture has unique characteristics that set them apart from one another. Homogeneous Mixtures A homogeneous mixture consists of particles that are evenly spread out or distributed. The components of a homogeneous mixture cannot be distinguished from each ather. This is because the particles of the components af a homogeneous mixture are so small that they cannot be seen by the naked eye. Homogeneous mixtures are also known as solutions. A solution is composed of a salute and a salvent. The solute is the substance that & dissolved by another substance, while the solvent = the dissoheng medium in which the solute dissolves. In a typical solution, the solvent is the mast abundant substance, while solute exists in smaller amounts. Substances that dissolve in a given solvent are Soluble. For instance, salt and sugar are both soluble in water since these substances dissoWwe when mixed thoroughly with water. Liquids that are soluble in each other at all proportions are miscible. Alcohol and water mix well as they are miscible, contrary to ail and water which are immecible. When a salute dissolves in a solvent, its particles are pulled x 2 7 away from one ancther. The particles of the salvwent penetrate [FSEN i o 5h robin the space between solute particles. As the solvent particles Fe a0kne the wh les Continue to surround the solute particles, both components solvent Is Water. are evenly spread out, creating a homogeneous mixture. KEYPOINTS LESSON 1.4 LESSON 1.5 SEPARATION OF MIXTURES Separation of Mixtures tH Introduction Without knowing i, you are routinely performing the preparation and separation of mixtures in your everyday life When you prepare our favorite powdered juice drink or when you mix ingredients when cooking your favorite dish, you are preparing mixtures. When you filter coffee from the coffee grind or pick out your favorite jelly bean flavor or color, you are separating mixtures. There are various ways to prepare and separate mixtures. Separation techniques for mixtures depend on its composition. These techniques usually take advantage of the differences in the physical and chemical properties of substances in a mixture. Familiarizing with the common separation techniques for mixtures will give you an appreciation for the importance of these methods in our daily lives. Separating Mixtures From the previous lesson, you learned that mixtures are combinations of two or more pure substances in which each substance retains its own composition and properties. They can be classified into two, homogeneous and heterogeneous. A homogeneous mixture is a combination of two or more substances that cannot be distinguished from each other. It has uniform composition and properties. Homogeneous solutions are also called solutions. On the other hand, a heterogeneous mixture is a combination of two or more substances that can be distinguished from each other. it has varying composition and properties. Heterogeneous mixtures can be further classified either as suspensions of colloids. A suspension is a heterogeneous mixture whose solutes do not completely dissolve. The ingoluble particles settle into clumps or layers when left undisturbed. A colloid is a heterogeneous mixture whose solute-like particles are dispersed in a medium. Each substance in a mixture has its own characteristic properties that are different from the set of properties of any other substance. And so, these properties can be taken advantage of in separating the components of a mixture from each other. In this lesson, you will learn about the different methods of separation for homogeneous and heterogeneous mixtures. Separating Homogeneous Mixtures Almost every sample of matter that you ordinarily encounter every day & a mixture. The combined substances in mixtures can be mixed in varied proportions. For a homogeneous mixture, its uniform appearance could suggest that it is *ure® in terms of composition. However, its one-phase appearance is due to the uniform distribution of its components all throughout This kind of mixture can be separated into simpler components Since homogeneous mixtures are prepared without any chemical reactions, its component: can be separated by physical mears. In this section, some separation techniques that can be employed in separating the components of homogeneous mixtures will be discussed. Evaporation Evaporation is the phase transition of matter from liquid to vapor. This separation technique is often employed to solid-liquid mixtures where a solid solute is dissolved in a liquid solvent In this process, a solution is heated until it boils. Once the solution bois, the liquid solvent starts to evaporate and leave behind the solid solutes. The case for solid solvents and liquid solutes separation can also take advantage of this separation technique. Recrystallization Recrystallization is a separation technique based on the difference in solubilities of substances in an appropriate solvent at an elevated temperature. Solubility refers to the amount of substance that can be dissoWed in a given solvent at a certain temperature. Recrystallization is often applied as a purification technique for solid mixtures. The method requires dissolving the solid compound in an appropriate soWent at an elevated temperature. The elevated temperature increases the solubility of the solute. This separates the solute of interest with another solute, which has low solubility in the solvent. Then, the solute starts to recrystallize as the solution cools down and being saturated by the solute. In the slow formation of the crystal lattice, the impurities are excluded. The collection of the crystals is then performed by another separation technique, filtration, which will be discussed further later. The choice of solvent is important in performing recrystallization as a separation technique. An ideal solvent for recrystallization must have the solute be soluble at high temperatures but only sparingly soluble at room or lower temperatures. The impurities must be insoluble in the solvent. Also, no reaction must occur between the solute and the soWent An ideal solvent is moderately volatile, and its boiling point is lower than the melting point of the solute. pot ep mp map mppm mu mmm mm mn mm mm vv mmm mmm mm mm mum mem mu mum TS mum vv err 1 I i i [| Remember In recrystallization, the solute must be soluble in the chosen solvent at high temperatures, but only sparingly soluble at room | I 1 ! temperature. ] Leese 8 8 SS SS Se Se ee Be ee eB EE EE EB ee ee EASE ee ee ee ee ee Distillation Distillation is a separation technique that is applied for homogeneous liquid-liquid mixtures. The separation is based on the difference in boiling points between the two liquid components. There must be a large difference between the boiling points of the components so that this separation technique can work. In this process, the component with the lower boiling point will evaporate first as the working temperature is raised, while the other remains as a liquid. The vapor then condenses and is collected in another container to separate the two components. The illustration below shows a distillation setup Separating acetone and water. distilling flask water outlet JEFF distillation setup The distilling flask is the laboratory glassware that is used to contain the mixture that will be distilled. In the acetone and water solution, acetome has a lower bolling point (56°C) compared to water (100°C). When the solution is boiled, the acetone vapor boils and evaporates first, leaving the water in the flask. The acetone vapor then moves through the condenser. The condenser aids in the condensation of the vapors or the change of vapors to liquids. Since cold water surrounds the inner tubing of the condenser, the acetone vapor cools down until it turns liquid again. The liquid acetone, fully separated from water, is collected in another container. The pure acetone that is collected i called the distillate or the product of distillation. The substance that remains in the distilling flask after distillation is called the residue. There are four common types of distillation processes—simple, fractional, vacuum, and steam. Simple distillation i used when there is a large difference in the boiling points of the components of the solution. It involves a single evaporation and condensation step. Fractional distillation is used when there is a relatively small difference in the boiling points of the components of the solution. It involves a series of evaporation and condensation steps. For compounds with very high boiling points, vacuum distillation is used. Steam distillation is used for compounds that are heat-sensitve. This enables the separation of the components before any components decompose. [I Remember There must be a large difference in the boiling points of the liquid components in order to perform distillation as a separation technique for liquid mixtures. Chromatography Another way to separate liquid-liquid mixtures is through chromatography. It is a Separation technique that relies on the differential partition of the components between the two important phases in chromatography: the mobile phase and the stationary phase. The mobile phase is the solvent in chromatography that carries the components throughout the stationary phase, an adsorbent material that holds the solutes still when interactions are favored. These two phases must have opposite polarities. Chromatography can be classified based on the polarity of its phases. In normal-phase chromatography, the mobile phase is nonpolar, and the stationary phase is polar. On the other hand, in reversed-phase chromatography, the mobile phase is polar, and the stationary phase is monpolar. The separation is determined by the two competing processes: the adsorption onto the Stationary phase and the solubility in the mobile phase. As the mobile phase runs through the stationary phase, the components of the mixture separate based on these competing processes. Whichever process is predominantly experienced by a molecule is dependent on the strength of its interaction with the stationary phase or the mobile phase. Solutes that have high solubility in the mobile phase will go along with the mobile phase as it travels on the stationary phase. On the other hand, solutes that have low solubility will tend te remain where they are. A Remember In normakphase chromatography, the mobile phase is nonpolar, and the stationary phase is polar. In reversed-phase chromatography, the mobile phase is polar, and the stationary phase is nonpolar. You may use the mnemonics NPSP for Normal Phase Stationary phase Polar. Chromatography can also be classified based on the structure of the stationary phase. In column chromatography, the stationary phase is held in a column. The mobile phase passes through the stationary phase by gravity or by applying pressure. In planar chromatography, the stationary phase is supported on a flat plate. The mobile phase moves via capillary action as it runs through the stationary phase upwards Below is an illustration of a paper chromatography setup, an example of planar chromatography. Here, the paper acts as the stationary phase and ethanol as the mobile phase. plece of wood pin ——— pager beaker ink spt water Start end A paper chromatography setup In paper chromatography, as the mobile phase runs through the paper upwards the components of the ink solution separate into its component dyes. The result of a chromatography experiment i called a chromatogram, which & a visual record of the result of the separation process. One can see from the illustration that the yellow dye component in the mixture has the highest solubility in the mobile phase, while the purple dye component has the least solubility. The chromatogram also suggests that the purple dye has the strongest adsorption on the stationary phase. A Remember In paper chromatography, the farther the solute travels in a chromatogram, the more it is soluble in the mobile phase. The shorter distance the solute travels means that it & more strongly adsorbed in the stationary phase. Separating Heterogeneous Mixtures Unlike solutions, heterogeneous mixtures have components that are visually distinct from each other. This is the reason why heterogeneous mixtures may be separated manually into its components. In this section, some separation techniques that can be employed in Separating the components of heterogeneous mixtures will be discussed. Manual Separation Heterogeneous mixtures with large, visible components may be separated into its components through manual separation techniques. Manual picking using your hands or tongs can be done in separating the components of these kinds of mixtures. They may be separated into various containers by picking them individually. For instance, you do manual picking when separating different non-biodegradables in a trash bin. Another manual separation technique is sieving. Separation by sieving takes advantage of the difference in particle size of solids. Asieve is a layer of holes that allow only certain sizes of particles to pass. An everyday example of a sieve is a kitchen sifter which is used for separating large clumps from fine flour particles. This technique is also applicable in separating sand from gravel before preparing a cement mixture. Some heterogeneous mixtures contain metallic components. These metallic components may be separated from the mixture by using a magnet. Iron and other metak are attracted to magnets. An example of a mixture that may be separated using a magnet ts iron filings and sulfur. When a magnet is placed near the mixture, the iron filings will be attracted to it, which will cause its separation from the sulfur. r i ' LJ Remember Separation using a magnet can only be done when separating metallic components that can be magnetized (paramagnetic). Presse Filtration Solid-liquid suspensions and colloids require more tedious techniques to be able to separate their components. Filtration i a process of separating solids from liquids by allowing the mixture to pass through a filtering material. Filters can be used to separate suspended solids from liquids. This is provided that the filter paper used has holes small enough for suspended solids mot to pass through. A common example of filtration is when you separate coffee grounds from brewed coffee. The coffee grounds are separated from the brewed coffee because its particles are too big to pass through the holes of the coffee filter. The coffee grounds collected on the filter paper is known as the residue while the brewed coffee is known as the filtrate. The filter paper to be used in filtering suspensions can be prepared in two manners: simple conical (3:1) or fluted filter paper. A 3:1 filter paper is a simple folded conical filter paper that is commonly used when filtering suspensions in which the solids are to be collected. It is prepared by taking a round piece of filter paper and folding it in half, then folding it again in half. The twice folded filter paper is opened to form a hollow cone that can be used for filtration. It is called 3:1 since the sheets of filter paper in the cone form must be separated by taking the three sheets together, leaving the other sheet alone. CO) @ D DEF Creating a 3:1 filter paper On the other hand, a fluted filter paper is used in gravity filtration when the filtrate or the liquid component i to be collected. It is prepared by taking a round piece of filter paper and folding it in half in multiple ways possible. It allows air to enter the flask along its sides to equalize pressure, thereby increasing the speed of filtration. It also provides a larger surface area through which the solvent can seep through. To show you how a fluted filter paper is prepared, watch the video below. ry DEF Creating a fluted filter paper - 1 ‘LJ Remember The conical 3:1 filter paper s commonly used when the solid component of a suspension is desired. The fluted filter paper is commonly used when the filtrate or the liquid component is ee desired, as it allows a faster filtration process. Sedimentation and Decantation Sedimentation is the process in which suspended solids will eventually separate from liquids by gravity. Once the solid particles settle at the bottom, the liquid may be separated through decantation. Decantation i the removal of the liquid component from solid sediment by pouring the liquid out of the container gently to avoid the solid particles to suspend again. It can be pumped out using a syringe or other suctioning device. Decantation may be aided with the use of a stirring rod to direct the flow of the solvent and prevent splashing. — Stirring rod Empty glass — Ee AL Decantation using a stirring rod Decantation may also be used to separate mixtures with liquids that are immiscible or do not mix well. An example of this is a mixture of oil and water. Since the water settles at the bottom, slowly pour out the oil from the container to separate it from water. An easier way to separate oll from water is by using a separatory funnel. It is used to separate two liquids with different densities. y* A separatory funnel is best used when separating two or more immiscible liquids. It works by decanting or allowing the liquid to flow past the stopper, collecting it in another container, and leaving the less dense liquid component in the separatory funnel. Centrifugation The components of solic-liquid suspensions and even colloids can be separated by centrifugation. Centrifugation is a process in which the suspension or colloid is rotated at very high speeds. It uses a machine called a centrifuge that rotates the sample. Centrifugation i often performed on suspensions or colloids in which the dispersed particles are small and do not settle at the bottom easily even when its left undisturbed. Initially, the particles are randomly dispersed in the medium, as shown in the figure below. But after loading the sample in the centrifuge, the centrifugal force pushes down the solids. After the process, the solid particles are separated from the liquid as they accumulate at the bottom of the container. The liquid can then be decanted to separate the solids from the liquid. Different liquids with different densities can be separated into layers using centrifugation as well. The layers can be separated from one another. Before After Centrifugation Centrifugation «nn (a) (b) EES Separation by centrifugation: (a) particles of a mixture before and after centrifugation, and (b) a centrifuge machine In the chemical and pharmaceutical industry, separation techniques are used to purify chemicals to acceptable standards. For example, in order for a medicine to be acceptable for use, it has to be purified to remove extremely toxic chemicals that were used to manufacture it. Medicines like paracetamol or aspirin, are recrystallized from solution to bring it to acceptable standards. In the petroleum industry, distillation is often used as a method to purify products. A refinery is an industrial site that is used to refine substances like oil, alcohol, and other substances. Crude oil is distilled to gasoline, kerosene and other petroleum products in order to be acceptable for applications. Petroleum products are used as fuel, which ts essential to the production of many other products and supports a comfortable way of modern living. [DEF A refinery where petroleum products are purified In the wastewater industry, separation techniques such as sedimentation, centrifugation, microfiltration, and distillation are used to recover water from used water. By doing so, harmful substances are removed before releasing the wastewater to the environment. Household water treatment includes the processing of tap water to separate water from contaminants making it Suitable for drinking. It may include separation methods such as filtration, sedimentation, and use of activated carbon. In this way, tap or faucet water becomes more suitable for drinking because of the removal of particulates, odor, color, and even some harmful, less persistent bacteria. However, it & advisable to check the water quality first before drinking any treated water. LESS es A water filtration system KEYPOINTS LESSON 1.5