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Science

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It comes from Latin word scire meaning “to know”. It is accumulated and systematized learning. It is a combination of both processes and products. The processes of science are scientific attitudes and scientific methods of inquiry whereas the products are the accumulated and systematized bodies of knowledge.

Aristotle

Greeks were probably the first to “create” science when they used deductive thinking in the investigation of phenomena. In fact, Thales of Miletus (640-546 B.C.), a Greek philosopher, astronomer, and engineer, originated the science of deductive geometry which was later developed and systematized by Euclid.

Technology

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This is an applied science. Techno comes from a Greek word referring to art and skill. Another Greek origin of technology is technologia, meaning “systematic treatment”.

Technology is older than science. When human being first fashioned tools from rocks to cope with their environment, which was technology in the primitive form. Our ancestors drank wine even before the process of fermentation was understood, Cleopatra, a Roman queen, used cosmetics and bathed in milk even before the science of cosmetology was known and developed.

Science belonged to the philosopher. Technology belonged to the tanners, millers, and silversmiths.

  • Thanks to Roger Bacon, an English Franciscan friar. He was a philosopher, scientist, and chemical experimentalist. He was known as a “wonderworker”. Science and technology began to grow closer in the 13th century.
  • The work of Faraday and Henry was used by Thomas Edison to invent the electric lamp.
  • The work of Helmholtz was used by Marconi to invent the telephone.
  • The work of Hertz and Maxwell was used by Marconi to invent the telegraph.
  • The work of Becquerel was used to develop the computerized axial tomography (CAT) and nuclear magnetic resonance (NMR).
  • The work of Einstein was used to develop nuclear energy and the atomic bomb.

Science, Technology and Society

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Science and technology greatly influenced human activities. Advances in communications like fax machines and cellular telephones. In transport systems like supersonic transport (SST) and bullet trains led to greater mobility. In medicine like organ transplants led to longer life expectancy.

Simply put, technology improved our standards of living, health, transportation systems, communications, etc. However, if abused, technology can also prove harmful. For example, it can cause environmental degradation. Its by-products can pollute and destroy the ecological balance of nature. So, we must not abuse the use of science and technology.

“What man has destroyed, man can repair”, it may eventually prove overoptimistic.

Chemistry

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It is a branch of science. Chemistry is the “central science”, it is necessary to understand the other science. Chemistry is the study of matter-it’s composition, structure, properties, transformation from one form to another, and the energy that accompanies its transformations.

Branches of Chemistry

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  • Organic Chemistry-It is concerned with the study of most carbon-based compounds.
  • Inorganic Chemistry-It deals with all substances which are not considered to be organic, which may contain any of the over 100 elements (including carbon).
  • Physical Chemistry-It deals with the application of physical laws to chemical change and chemical systems.
  • Biochemistry-It is considered with the chemistry of life processes and living organisms.
  • Analytical Chemistry-It is concerned mainly with the various techniques and laboratory methods to determine the composition of matter.

Careers in Chemistry

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  • - Careers in Industry-Many industries are chemical-based like food, petroleum, cosmetic, pharmaceutical, biotechnology, mining etc.
  • - Careers in Commerce-A chemistry degree is a good training to acquire skills in mathematics, problem-solving, communication, research, self-management etc.
  • - Careers in Journalism-Science are journalists narrow the gap between science, technology and the public.
  • - Careers in Law/Forensics-Chemists are an important role in solving crimes that involve forgery, death, arson, paternity etc.
  • - Careers in Teaching-Chemists who are effective instructional skills are valuable in educating students about the world of chemistry and its roles in improving life and environment.
  • - Careers in Entrepreneurship-Chemists with technical know-how on preparation development and quality assessment of products may be able to establish small and medium industries.
  • - Careers in Health/Science Related Professions-Because of their intensive chemical/scientific background and skills, chemists can easily take on rigorous training to enter health/science0related professions like nursing, dentistry, psychology and nutrition.

Filipino Chemists and Their Habits of Mind

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  • - Julian Banzon his contribution on the production of alternative fuels and in the extraction of residual coconut oil by chemical means rather than physical means.
  • - Francisco Santos for his studies on the nutritive values and chemical compositions of local foods in the Philippines, which helped in detecting and solving problems associated with Filipino diets.
  • - Francisco Quisumbing for his inventions of Quink ink, a quick drying ink with cleaning properties, used in Parker pens.
  • - Luz Oliveros Belardo for the extraction of essentials oils and her studies of their chemical and physical properties, which are applied in herbal medication and creation of synthetic flavors.
  • - William Padolina for his works in phytochemistry like extraction of natural insecticides from indigenous plants, preparation of new fatty acid derivatives, biogas generation from crop residues etc.
  • - Gerardo Janairo for developing new routes to pharmacologically interesting organic compounds which has impact on the syntheses of antibiotics and analogs.
  • - Concepcion Lizada for her contribution in the generation of information development of technologies that help in the reduction of postharvest losses of tropical fruits and vegetables.
  • - Fortunato Sevilla III for his works on chemical sensors and biosensors used in the analysis and development of low-cost instrumentation for chemical education.
  • - Elma Llaguno for her studies on organic pollutants in the environments and human substance in soil, sediment, and water.
  • - Gloria de Castro Bernas for her investigation of Philippine plants in the management of cancer.
  • - Evelyn Mae Tecson Mendoza for her researches on molecular mechanism of plant resistance to pests and diseases, biochemical factors affecting nutritional basis of the makapuno phenotype of coconut.
  • - Beatrice Guevarra for her work on natural products especially alkaloid-bearing plants in the Philippines rainforest.

Habits of Mind: Scientific Attitudes and Scientific Methods

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Scientific Attitudes

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  • - Curiosity-ability to seek, inquire and discover.
  • - Determination-being persistent, firm and self-confident.
  • - Open-mindedness-being open to new ideas even those from unlikely or unexpected sources.
  • - Acceptance of results-whether desired or undesired—there is no such this as ‘failure’ in a scientific investigation.
  • - Objectivity-being impartial and remaining influenced by anything but pertinent physical observations.
  • - Humility-being modest and unassuming.
  • - Skepticism-being doubtful unless presented with reliable data.
  • - Patience-ability to wait calmly for the result of the investigation.
  • - Reflection-being able to monitor and assess one’s behavior/action.
  • - Empathy for human condition-putting oneself in the position of another person.
  • - Observation-means to investigate the object being studied.
  • - Defining Problem-it refers to a query regarding an observation.
  • - Formulating Hypothesis-It is an educated guess explaining an observation.
  • - Experimentation-A given question may have a thousand possible answers but only onw right answer.
  • - Theory-These are extensively tested and used to describe a model and also questioned and tested by new experiments.

Units of Measurement

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The Systeme International d’ Unite, or SI (system of units), is adopted all over the world. It is simple and convenient to use since all units are based on multiples of 10. The SI system is a modified form of metric system.

Table 1-1: Prefixes SI Prefixes.

Prefix Symbol Multiplier

exa E 〖10〗^18

deci d 〖10〗^(-1)

peta P 〖10〗^(15)

*centi c 〖10〗^(-2)

tera T 〖10〗^(12)

*milli m 〖10〗^(-3)

giga G 〖10〗^(9)

*micro µ 〖10〗^(-6)

mega M 〖10〗^(-1)

nano n 〖10〗^(-9)

kilo k 〖10〗^(3)

pico p 〖10〗^(-12)

hecto h 〖10〗^(2)

femto f 〖10〗^(-15)

deka da 〖10〗^(1)

atto a 〖10〗^(-18)


Unit of Distance

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1. Kilometer (km) is used to measure long distances

2. Centimeter (cm) is used for short distances.

Unit of Volume

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1. Cubic meter (m^3)

2. Liter (L) and milliliter (mL) – non-SI units, commonly used units of volume.

3. Cubic centimeter (cc or 〖cm〗^3) – has the same volume as a milliliter.

Unit of Mass

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1. Kilogram (kg)

Unit of Time

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1. Second (s)

2. Hour (hr)

3. Minute (min)

Unit of Temperature

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1. Kelvin (K) – named after the British scientist William Thomson, Baron Kelvin of Largs.

2. Degree Celsius (℃)

3. Degree Fahrenheit (℉) – formerly degree centigrade.


Boiling point of water 100 ℃ 212℉ 373 K

Freezing point of water 0℃ 32℉ 273 K

Absolute Zero -273℃ 459 ℉ 0 K


Equations:

  • • ℃ = K-273
  • • K = ℃+273
  • • ℃ = 5/9(℉-32)
  • • ℉ = 9/5(℃+32)

No measurement is exact. Uncertainty exists in all measurements. When numbers are obtained from measurements, the number of digits given depends on the limits of accuracy of the measuring instruments used.

In dealing with numbers obtained from measurements, the following rules are applied:

  • All nonzero digits are significant.
  • Zeros between nonzero digits are significant.
  • Zeros after a significant digit and after a decimal point are significant.
  • Zeros to the left of nonzero digits are not significant but are used to indicate the position of the decimal point.
  • When a number ends in zeros, the zeros are significant unless they appear to the right of a decimal point.
  1. "When adding or subtracting: it depends on the least decimal places."
  2. '''When multiplying or dividing: it depends on the least significant figures."

Scientists often deal with very small or very large numbers. For convenience in calculation, you can transform these numbers into scientific notation. Scientific notation is a combination of two numbers. The first number is a decimal number between 1 and 10. This is followed by a multiplication sign (x). The second number, called exponent, is a power of 10 then followed by the unit needed.

Example:

  1. 13 000=1.3 x 〖10〗^4
  2. 8 000 000=8 x〖 10〗^6
  3. 18 234=1.8234 x 〖10〗^4
  4. .49173=4.9173 x 〖10〗^(-1)
  5. .00000039158= 3.9158 x 〖10〗^(-7)

It is derived from an existing relationship between two units of measurement. It is written or expressed in fraction form having a numerator and denominator. It is used to produce the desired cancellation of unit.

Unit sought for = unit given x conversion factor

Example:

  1. 13 km - m = (13 km)/1 x (1 000 m)/(1 km) = 13 000 m

Density is the mass of a unit volume of a sample. It can be calculated by dividing the total mass of the sample by its volume.

  1. d=m/v
  2. v= m/d
  3. m= d x v

Tools in Science

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Among the equipment and apparatus you will use in the laboratory are the following:

Glassware

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Beaker

> may be used as containers because most chemicals do not react with glass.

1. Beaker - a simple container for stirring, mixing and heating liquids commonly used in many laboratories.

2. Buret - use for burets is in titrations.

3. Erlenmeyer Flask - used in chemistry labs for titration.

4. Florence Flask - used as a container to hold liquids.

5. Graduated Cylinder - used to measure the volume of a liquid.

6. Pipet - used in chemistry, biology and medicine to transport a measured volume of liquid.

Laboratory Glasswares

7. Test Tubes - widely used by chemists to hold, mix, or heat small quantities of solid or liquid chemicals, especially for qualitative experiments and assays.

8. Stirring Rod - used to mix chemicals and liquids for laboratory purposes.

9. Reagent Bottles - are containers made of glass, plastic, borosilicate or related substances, and topped by special caps or stoppers and are intended to contain chemicals in liquid or powder form for laboratories and stored in cabinets or on shelves.

Auxiliary Glasswares/Plasticwaes/Porcelainwares

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10. Crucible - used for metal, glass, and pigment production as well as a number of modern laboratory processes.

11. Filter Funnel - used for separating solids from liquids via the laboratory process of filtering.

12. Mortar and Pestel - used for crushing and grinding.

13. Evaporating Dish - used to evaporate excess solvents, most commonly water - to produce a concentrated solution or a solid precipitate of the dissolved substance.

14. Thermometer - measures temperature or temperature gradient using a variety of different principles.

15. Wash Bottle - used to rinse various pieces of laboratory glassware, such as test tubes and round bottom flasks.

16. Watch Glass - used in chemistry as a surface to evaporate a liquid, to hold solids while being weighed, or as a cover for a beaker.

Auxiliary Equipment

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17. Clay Triangle - used for supporting crucibles when they are heated.

18. Crucible Tongs - used to take crucibles out of fire.

19. Spatula - uses a laboratory spatula to mix solutions and scoop materials.

20. Iron Ring - used in chemistry labs to stabilize flasks mounted to a ring stand.

21. Iron Stand - supports the iron ring when heating substances or mixtures in a flask or beaker.

22. Test tube Brush - used for cleaning the bottom and inner side of the test tubes

23. Test tube Holder - to hold test tubes during various experiments.

Alcohol Lamp

24. Test tube Rack - used to hold test tubes, and sometimes pipettes, that contain chemicals that are awaiting further action.

25. Tripod - this stand is often use in chemistry, biology and physics laboratory experiments that usually involves burning or having some objects under the flame.

26. Wire Gauze - it prevents the heat of the apparatus directly. The circle thing on the wire gauze ensures that the heat is spread everywhere

Sources of Heat

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27. Alcohol Lamp - used to heat objects in laboratories as well as in the repairing of pens and also used to provide light.

28. Bunsen Burner - used for heating, sterilization, and combustion.

Triple-beam Balance

Measuring

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29. Platform Balance - used to weigh things. Use the links to discover more information and to see images of the device.

30. Triple-beam Balance - used to measure masses very precisely; the reading error is 0.05 gram.