Separating Mixture and Component Substances

Filtration

Filtration is commonly the mechanical or physical operation which is used for the separation of solids from fluids (liquids or gases) by interposing a medium through which only the fluid can pass. Oversize solids in the fluid are retained, but the separation is not complete; solids will be contaminated with some fluid and filtrate will contain fine particles (depending on the pore size and filter thickness). Filtration is also used to describe some biological processes, especially in water treatmentand sewage treatment in which undesirable constituents are removed by adsorption into a biological film grown on or in the filter medium.

Mechanical Separation

Mechanical separation is any process that separates elements or compounds in a mixture through mechanical rather than chemical means.

Decantation

Decantation is a process for the separation of mixtures. This is achieved by carefully pouring a solution from a container in order to leave theprecipitate (sediments) in the bottom of the original container. Usually a small amount of solution must be left in the container, and care must be taken to prevent a small amount of precipitate from flowing with the solution out of the container. It is generally used to separate a liquid from an insoluble solid (e.g. in red wine, where the wine is decanted from the potassium bitartrate crystals).

Evaporation

Evaporation is a type of vaporization of a liquid that occurs only on the surface of a liquid. The other type of vaporization is boiling, which, instead, occurs on the entire mass of the liquid. Evaporation is also part of the water cycle.

Distillation 

Distillation is a method of separating mixtures based on differences in their volatilities in a boiling liquid mixture. Distillation is a unit operation, or a physical separation process, and not achemical reaction.

Chromatography

Chromatography  is the collective term for a set of laboratory techniques for the separation of mixtures. It involves passing a mixture dissolved in a "mobile phase" through a stationary phase, which separates the analyteto be measured from other molecules in the mixture based on differential partitioning between the mobile and stationary phases. Subtle differences in a compound's partition coefficient result in differential retention on the stationary phase and thus changing the separation.

Evidence of Chemical Change

Magnesium

Magnesium metal and alloys are highly flammable in their pure form when molten, as a powder, or in ribbon form. Burning or molten magnesium metal reacts violently with water. Magnesium powder is an explosive hazard. One should wear safety glasses while working with magnesium, and if burning it, these should include a heavy U.V. filter, similar to welding eye protection. The bright white light (including ultraviolet) produced by burning magnesium can permanently damage the retinas of the eyes, similar to welding arc burns.

Water should not be used to extinguish magnesium fires, because it can produce hydrogen which will feed the fire.

Carbon dioxide fire extinguishers should not be used either, because magnesium can burn in carbon dioxide (forming magnesium oxide, MgO, and carbon). A Class D dry chemical fire extinguisher should be used if available, or else the fire should be covered with sand or magnesium foundry flux. An easy way to put out small metal fires is to place a polyethylene bag filled with dry sand on top of the fire. The heat of the fire will melt the bag and the sand will flow out onto the fire.

Calcium

Chemically calcium is reactive and moderately soft for a metal (though harder than lead, it can be cut with a knife with difficulty). It is a silvery metallic element that must be extracted by electrolysis from a fused salt like calcium chloride.Once produced, it rapidly forms a grey-white oxide and nitride coating when exposed to air. It is somewhat difficult to ignite, in character rather like magnesium, but when lit, the metal burns in air with a brilliant high-intensity red light. Calcium metal reacts with water, evolving hydrogen gas at a rate rapid enough to be noticeable (unlike its sister magnesium) but not fast enough at room temperature to generate much heat. Part of the slowness of the calcium-water reaction results from the metal being partly protected by insoluble white calcium hydroxide. In water solutions of acids where the salt is water soluble, calcium reacts vigorously.

Strontium 

An alkaline earth metal, strontium is a soft silver-white or yellowish metallic element that is highly reactive chemically. The metal turns yellow when exposed to air.

Due to its extreme reactivity to air, this element occurs naturally only in compounds with other elements, as in the minerals strontianite and celestite.

In its pure form strontium is extremely reactive with air and spontaneously combusts. It is therefore considered to be a fire hazard.

The human body absorbs strontium as if it were calcium. Due to the elements being sufficiently similar chemically, the stable forms of strontium do not pose a significant health threat, but the radioactive ⁹⁰Sr can lead to various bone disorders and diseases, including bone cancer.

Barium

Barium is a soft silvery metallic alkaline earth metal. It is never found in nature in its pure form due to its reactivity with air. Its oxide is historically known as baryta but it reacts with water and carbon dioxide and is not found as a mineral.

Barium is a metallic element that is chemically similar to calcium but more reactive. This metal oxidizes very easily when exposed to air and is highly reactive with water or alcohol, producing hydrogen gas. Burning in air or oxygen produces not just barium oxide (BaO) but also the peroxide. Simple compounds of this heavy element are notable for their high specific gravity. This is true of the most common barium-bearing mineral, its sulfate barite BaSO₄, also called 'heavy spar' due to the high density (4.5 g/cm³).

All water or acid soluble barium compounds are extremely poisonous. At low doses, barium acts as a muscle stimulant, while higher doses affect the nervous system, causing cardiac irregularities, tremors, weakness, anxiety, dyspnea and paralysis. This may be due to its ability to block potassium ion channels which are critical to the proper function of the nervous system.

Foreign Chemistry

Antoine Henri Lavoisier

Antoine Lavoisier is also known as “The Father of Modern Chemistry”. He was a French nobleman prominent in the histories of chemistry and biology. He stated the first version of the Law of Conversion of mass, recognized and named oxygen in 1778 and also recognized and named hydrogen in 1783. He proved that oxygen played the major role in the differences in weight associated with combustion, disproving the accepted view of the Phlogiston Theory. He helped construct the metric system, wrote the first extensive list of elements, and helped to reform chemical nomenclature.

Joseph Priestly

Nitrous oxide ("laughing gas") was first synthesized by English chemist and natural philosopher Joseph Priestley. Priestley describes the preparation of "nitrous air diminished" by heating iron filings dampened with nitric acid in Experiments and Observations on Different Kinds of Air. 3 vols. London, (1775). Priestley was delighted with his discovery: "I have now discovered an air five or six times as good as common air... nothing I ever did has surprised me more, or is more satisfactory." But unlike Humphry Davy, Priestley didn't try inhaling gas to explore its psychoactive effects.

Priestley further isolated and described the properties of carbon dioxide, hydrochloric acid, carbon monoxide, sulfur dioxide and "dephlogisticated air". He corresponded with Antoine Lavoisier, who debunked phlogiston theory and re-named "dephlogisticated air" as oxygen. Priestley identified the gases involved in plant respiration, and observed photosynthesis. He also discovered that graphite is a conductor of electricity; and invented a very drinkable beverage of carbonated water, i.e. soda pop.

In the 18th century, doctors had very little idea of what caused disease. Its symptoms could sometimes be palliated, but cures were rare. So doctors and other assorted medical men eagerly experimented with the new gases and the vapours of volatile liquids to discover if they conferred any therapeutic benefits, especially for respiratory disease. One of the most prominent investigators was Thomas Beddoes, founder of the Pneumatic Institution (1798).

Dorothy Hodgkin

The sole Nobel Laureate in Chemistry in 1964, she was the third woman and the first Englishwoman to receive it. It was given for her work in X-ray crystallography, determining the structures of steroids, penicillin, and vitamin B₁₂; she later determined the structure of insulin in collaboration with Chinese scientists. Hodgkin always pushed the X-ray method to the limits of its capabilities; the B₁₂ structure, for example, was by far the most complex that had been worked out at the time, long before current computer methods were developed. She went to Oxford University in 1928 when few women studied science, did her Ph.D. at Cambridge and returned to Oxford for most of her career. She helped scientists in India, China and Africa, and worked for peace as president of the "Pugwash" conferences and the BAAS.

William Ramsay

Extracted 5 noble gases from the air

• Argon-inactive
• Neon-New
• Xenon-Stanger
• Krypton- Hidden
• Helium- Sun

Louis Pasteur

Worked on fermentation and decay a led to the development of the germ theory of disease and to the sterilization of food through the use of heat. 

Filipino Heroes in Chemistry

Julian A. Banzon

Dr. Banzon has done a great deal of work on local materials especially coconut as the renewable source of chemicals and fuels. His work on the production of ethyl esters from sugarcane and coconut is the first study on fuels from these crops. He also devised some novel processes noteworthy among these is the extraction of residual coconut oil by chemical, rather than by physical processes  

For these and many more significant scientific works, Dr. Banzon has been accorded honors and citations notably: Distinguished Service Award, Integrated Chemist of the Philippines, Inc. (1980), Chemist of the Year Award, Professional Regulation Commission (1978) and the PHILSUGIN Award for research, Crop Society of the Philippines, 1976.

Conrado S. Dayrit

Dr. Conrado S. Dayrit will receive the Lux in Domino Award in recognition of his commitment and dedication to the pursuit of scientific studies and clinical trials on Philippine herbs including the benefits of virgin coconut oil, leading to the development of low cost medicines which have become accessible to the poor. The Award highlights his intellectual legacy and scholarly work recognized by local and international scientific bodies. The Award recognizes the Catholic ideals he has exhibited throughout his professional and personal life. (Pharmacologist and cardiologist). 

Luz Oliveros Belardo

Research on essential oils from plant extracts as source of medicine, fragrance for perfumes, food flavorings and liquid fuel for energy.

• Tanglad- diuretic
• Apitong & Pili Trees- Petroluem-like products
• Chichirica- anti-cancer alkaloid

Engr. Felix Maramba

He built a coconut oil-fueled power generator, which we can use in our life and we can lessen the pollution because of that generator. Felix wants to save our environment. Felix also wrote about biogas and waste recycling to warning and guide us how to save many things, to lessen the damage of our environment and the more important is to save it from the pollution that we make.

Arturo Alcaraz

Considered as the Philippines' Father of Geothermal Energy Development, due to his contributions to studies about Philippine volcanology and the energy derived from volcanic sources. Alcaraz started as an aide in the Geology division of the Bureau of Mines, and after further education ascended to the positions of Assistant Geologist and Chief Geophysicist in different government agencies. His chief contribution was the study and establishment of geothermal power plants in the country, particularly in the regions of Tiwi, Albay, Mt. Makiling and Mt. Banahaw (Mac-Ban), and Leyte. In the 1980s, the Philippines even attained the second highest geothermal generating capacity in the world, besting mentor countries Italy and New Zealand.

Eduardo A. Quisumbing

From 1920-26 he was attached to the College of Agriculture in U.P., and from 1926-28 to the University of California; in 1928 appointed Systematic Botanist and since February 1934 Acting Chief of the Natural Museum Division of the Bureau of Science, Manila, now Director of the National Museum. When assigned to the U.S. Navy in Guiuan, at the southern tip of Samar, made collections in that region. He retired as Director in November 1961, and was for some following years attached to the Araneta University. Dr. Quisumbing undertook restoration of the Herbarium which was completely destroyed during the war.

Dr. Quisumbing was author of taxonomic and morphological papers, many of which deal with orchids, including ‘Medicinal plants in the Philippines’ (Manila 1951).Saccolabium quisumbingii has been named in his honour. He was recipient of the Distinguished Service Star (1954) for outstanding contribution to the field of systematic botany; Diploma of Merit on Orchidology and Fellow Gold Medal, Malaysian Orchid Society (1966); Gold Medal, American Orchid Society and 1975 PhilAAS Most Outstanding Award.

Dr. Evelyn Mae T. Mendoza

Dr. Tecson-Mendoza‘s research interests cover molecular mechanisms of plant resistance to pests and diseases, biochemical factors affecting nutritional quality and acceptability of plant foods, and plant biochemistry, molecular biology and biotechnology and their applications in plant breeding. She has, with co-researchers and students, published more than 90 technical papers in refereed journals, has co-authored two books, edited or co-edited five books, and has written 12 chapters in various books. Dr. Tecson-Mendoza is the recipient of several national, professional, and institutional awards and research paper awards. She is presently the editor-in-chief of the ISI-covered Philippine Agricultural Scientist.