Science

◊Chemistry: study of composition, structure, properties, interactions of matter

◊Branches of Chemistry:

◊Organic-carbon compounds and their reactions; farms, fertilizers, living things, synthetic fibres; all living things have carbon but not all things with carbon are living

◊Inorganic - not containing carbon; H, S, Mg (non-livving things)

◊Biochemistry: found in living organisms; reactions underlying life processes; Organic

◊Geochemistry: composition of rocks, ores, mining or petroleum; Inorganic

◊Astrochemistry: compostion of heavenly bodies; Inorganic

◊Analytical chemistry: to analyze compositions of samples (forensics); Qualitative (components, structure, properties); Qualitative (amount of substance present);Organic/Inorganic

◊Physical Chemistry: physical properties; Inorganic/Organic

            ◊Thermodynamics: heat-energy changes accompanying a reaction

          ◊Chem. Kinetics: rate of chemical reactions

          ◊Electrochemistry: electrical properties

◊Environmental Chemistry: organic/inorganic; soil, pollution, fertilizer

◊Nuclear Chemistry: inorganic; radioactivity; sub-atomic particles; nuclear reactions

◊Pharmaceutical Chemistry: manufacture of drugs; inorganic/organic

◊Polymer Chemistry: deals with synthetic macromolecules like plastic, nylon; organic/inorganic

For Measurements and Significant Figures, please refer to book&notes

LESSON 1

◊Aristotle: human beings by nature desire to know

◊Science: comes from Latin word scire meaning “to know”; accumulated and systematized larning; combination of both processes and products

◊Greeks: probbaly first to create science

◊Thales of Miletus: Greek philosopher, astronomer, engineer orginated the science of deductive geometry which was later developed by Euclid

◊Technology: applied science; coems from Greek word “techno” meaning art and skills or “technologia” meaning systematic tratment

◊Examples of how technology came before science: wine fermentation; Cleopatra bathing in milk

◊Roger Bacon: English Franciscan friar; philosopher, scientist, chemical experimentalist; made science closer to technology, “wonder worker”

◊Nineteenth century:marked beginning of applied science

Examples of use of science in technology

◊Edison’s electic lamp; work of Faraday and Henry

◊Bell’s telephone; work of Helmholtz

◊Marconi’s telegraph; work of Hertz and Maxwell

◊Computerized axial technology (CAT) and nuclear magnetic resonance (NMR); work of Becquerel

◊Atomic bomb; work of Einstein

Scientific Attitudes

◊Curiosity                    ◊Determination

◊Open-mindedness      ◊Acceptance of failure

◊Objectivity                 ◊Humility

◊Skepticism                 ◊Patience

Scientific Method in Book:

◊Scientific law: verbal or mathematical statement which relates a series of observations that have been verified again and again; is permanent does not change

◊Theory: hypotheses extensively tested and used to describe a model; questioned and tested by new experiments; always remains tentative

◊Scientific model: picture of representation of what we cannot see

Three-step scientific method

◊Observation               ◊Representation                      ◊Interpretation

Women Scientists

◊Marguerite Perey: French chemist; discovered in 1939 francium; elected to French Academy of Science

◊Dorothy Hodgkin: Nobel Prize for Chemistry; structure of biochemicla compounds essential in combating pernicious anemia

◊María Geoppert Mayer: with Hans Jensen and Eugene Wigner; Nobel Prize for physics for work on nuclear structures

◊Giuliana Tesora: science and technology of polymers; 100 Us patents

◊Beatrice Q. Guevarra: alkaloi-dbearing plants in Philippine rainforest

◊Evelyn Mae T. Mendoza: plant biochemistry; chemical and biochemical factors that affect nutritional quality

◊Elma C. Llaguno: director of National Science Research Institute; basic researches in different fields of Science

For Measurements and Significant Figures, please just refer to book and handouts

LESSON 2 BOOK ONLY

◊Matter: anything that takes up space and has mass; solid, liquid, gas

◊Solids: spoons, tires, dry ice

◊Liquids: milk, gasoline, rubbing alcohol

◊Gases: steam, chlorine, oxygen

◊Evaporation: liquid changing to gaseous state

◊Condensation: gas into liquid

◊Different liquids show different rates of evaporation because theforces of attraction between the molecules are not the same in all liquids

◊Sublimation: solid to gas; mothballs, dry ice

◊Dry ice: solid carbon dioxide; has high rate of sublimation

◊Salts/metals: have very low rates of sublimation

◊Refrigeration: effective metod of retarding bacterial activity in foods by reducing temperature

◊Physical change: change in appearance or physical form

◊Chemical change: change in chemical composition

◊Heterogeneous: materials with parts that are composed of different properties; wet sand; granite rock; concrete and soil

◊Homogeneous: materials that have parts that are all alike; properties of one part identical with the others; table salt, dust-free air, charcoal, silver, filtered ocean water, alloys

◊Matter: either pure substances or mixtures

Elements

◊109 different elements; 88 naturally occuring

◊Elements: fundamental substances from which all things are built and cannot be broken down into simpler substances

◊Names: uranium from planet uranus, curium from Marie Curie, iodine from Greek word ioeides, and magnesium from mineral, magnesia

Physical Properties

◊Extensive properties: depend on the amount of material like mass, length and volume

◊Intensive properties: depend on quality of material like odor, color, specific gravity, solubility, density, boiling point, melting point, electrical conductivity

Chemical Properties

◊chemical changes

Compounds

◊cannot be separated into other substances by physical methods; and the elements in it are always in fixed proportions

◊Exothermic: heat release

◊Endothermic: heat absorption

Importance of Some Elements and Compounds

◊Trace elements: elements needed in smaller quantities

◊Calcium/phosphorus: essential for bones and teeth

◊Calcium: regulates blood clotting and muscle action

◊Fluorine: prevents tooth decay

◊Iodine: important for thyroid gland

◊Oxygen: reacts with carbon compounds in the body cells to produce heat and energy during respiration

◊Water: 70% of mass of our bodies; eliminates toxins in our body especially in our kidneys

Elements and compounds in Industry

◊Alloys of magnesium and zinc: cars, aircraft, flares, flashbulbs, fireworks

◊Aluminum: non-toxic metal for utensils; aircraft, ships; welding irons

◊Aluminum hydroxide: mordant dyeing; making dye fixed on material

◊Lead: shield against radioactive materials, car batteries

◊Diamond: abrasive in saws drills, and grinding wheels; drill crowns

◊Oxygen: manufacture of steel and paper; welding; water purification

◊Chroline: water treatment; chlorinated hydrocarbons, pulp and paper

◊Silica: main component of sand; inorganic polymer of silicon and oxygen; glass; insulating material for electrical wiring in defense applications; medicine and cosmetic surgery

◊Sulfuric acid: fertilizer production; synthesis of chemicals in petroleum refining

◊Calcium oxide: glass; cement, water purification

◊Calcium carbonate: chalk; limestone; marble; quicklime; toothpaste

◊Chloride, bromide, iodide (three halides): photograpic films and papers; silver bromide works best as it reactly less quickly to light

◊Sodium hydroxide: manufacture of chemicals, paper, aluminum, petroleum, soap, detergents

Methods of Separating Components of Mixtures

Filtration

◊process of sperating the insoluble solid from the liquid

◊filter paper allows liquids to pass through and retains solid particles

◊solid particles: residue

◊glass funnel used as support for filter paper

Mechanical Separation

◊involves use of forceps, sieves, and other si,ilar tools; separation of gravel and sand

Flotation

◊method in which some solids of a suspension mixtures are allowed to settle and the less dense material is poured off

◊ex: panning of gold (practiced in Southern Philippines)

Centrifugation

◊speeds up settling of precipipate

◊centrifuge: motor-driven apparatus; centripetal force developed during rotation bring precipitate to bootm of tube

◊centrifugate: supernatant liquid poured off

Distillation

◊process that involves the evaporation and condensation of volatile liquid

◊more volatile liquid boils off first, evaporates then condenses

◊distillate; liquid formed the condensation of the vapor

◊used to make distilled water

Fractional Distillation

◊used to separate a liquid mixture with a small range of boiling points

◊separated in decreasing order of boiling points

◊Crude oil is separated into fractions of gasoline, kerosene, lubricating oil

Fractional Crystallization

◊lowering of temperature so that the more insoluble component crystallizes out first

◊solid is remoed by filtration

◊temperature is lowered until no more solid crystallizes

Chromatography

◊uses difference in degree to which substances are absorbed on the surface of an inert substance

◊Adsorption chromatography: column and thin layer chromatography

◊drop of black ink or green extract will be separated into different components if spotted at the end of a filter paper and the tip of the paper is to barely touch the solvent

Laws of Chemical Combination

◊Law of Conservation of Mass: masses of reactions equals to masses of products

◊Albert Einstein: E=mc2; e=energy, m=mass, c=velocity of light

◊Law of Definite Composition or Definite Proprtions: given compound always has a fixed proportion

◊Law of Multiple Proportions: When two elements combine to form more than one compound, the masses of one elements which combine with a fixed mass of the other element are in a ratio of small whole numbers such as 2:1, 1:1, 2:3, etc.

Acids vs. Bases

Acids:

◊ph less than 7

◊releases hydrogen ions when in solution

◊turns blue litmus red

◊corrosive and sour

Bases:

◊ph value between 8 and 14

◊turns red litmus blue

◊bitter tasting

For Protons……please refer to notes