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When it was his turn to speak, Adam Malik, Presidium Minister for Political Affairs and Minister for Foreign Affairs of Indonesia, recalled that about a year before, in Bangkok, at the conclusion of the peace talks between Indonesia and Malaysia, he had explored the idea of an organization such as ASEAN with his Malaysian and Thai counterparts. One of the “angry young men” in his country’s struggle for independence two decades earlier, Adam Malik was then 50 years old and one of a Presidium of five led by then General Soeharto that was steering Indonesia from the verge of economic and political chaos. He was the Presidium’s point man in Indonesia’s efforts to mend fences with its neighbors in the wake of an unfortunate policy of confrontation. During the past year, he said, the Ministers had all worked together toward the realization of the ASEAN idea, “making haste slowly, in order to build a new association for regional cooperation.” Adam Malik went on to describe Indonesia’s vision of a Southeast Asia developing into “a region which can stand on its own feet, strong enough to defend itself against any negative influence from outside the region.” Such a vision, he stressed, was not wishful thinking, if the countries of the region effectively cooperated with each other, considering their combined natural resources and manpower. He referred to differences of outlook among the member countries, but those differences, he said, would be overcome through a maximum of goodwill and understanding, faith and realism. Hard work, patience and perseverance, he added, would also be necessary. The countries of Southeast Asia should also be willing to take responsibility for whatever happens to them, according to Tun Abdul Razak, the Deputy Prime Minister of Malaysia, who spoke next. In his speech, he conjured a vision of an ASEAN that would include all the countries of Southeast Asia. Tun Abdul Razak was then concurrently his country’s Minister of Defence and Minister of National Development. It was a time when national survival was the overriding thrust of Malaysia’s relations with other nations and so as Minister of Defence, he was in charge of his country’s foreign affairs. He stressed that the countries of the region should recognize that unless they assumed their common responsibility to shape their own destiny and to prevent external intervention and interference, Southeast Asia would remain fraught with danger and tension. And unless they took decisive and collective action to prevent the eruption of intra-regional conflicts, the nations of Southeast Asia would remain susceptible to manipulation, one against another. “We the nations and peoples of Southeast Asia,” Tun Abdul Razak said, “must get together and form by ourselves a new perspective and a new framework for our region. It is important that individually and jointly we should create a deep awareness that we cannot survive for long as independent but isolated peoples unless we also think and act together and unless we prove by deeds that we belong to a family of Southeast Asian nations bound together by ties of friendship and goodwill and imbued with our own ideals and aspirations and determined to shape our own destiny”. He added that, “with the establishment of ASEAN, we have taken a firm and a bold step on that road”. For his part, S. Rajaratnam, a former Minister of Culture of multi-cultural Singapore who, at that time, served as its first Foreign Minister, noted that two decades of nationalist fervor had not fulfilled the expectations of the people of Southeast Asia for better living standards. If ASEAN would succeed, he said, then its members would have to marry national thinking with regional thinking. “We must now think at two levels,” Rajaratnam said. “We must think not only of our national interests but posit them against regional interests: that is a new way of thinking about our problems. And these are two different things and sometimes they can conflict. Secondly, we must also accept the fact, if we are really serious about it, that regional existence means painful adjustments to those practices and thinking in our respective countries. We must make these painful and difficult adjustments. If we are not going to do that, then regionalism remains a utopia.” S. Rajaratnam expressed the fear, however, that ASEAN would be misunderstood. “We are not against anything”, he said, “not against anybody”. And here he used a term that would have an ominous ring even today: balkanization. In Southeast Asia, as in Europe and any part of the world, he said, outside powers had a vested interest in the balkanization of the region. “We want to ensure,” he said, “a stable Southeast Asia, not a balkanized Southeast Asia. And those countries who are interested, genuinely interested, in the stability of Southeast Asia, the prosperity of Southeast Asia, and better economic and social conditions, will welcome small countries getting together to pool their collective resources and their collective wisdom to contribute to the peace of the world.” The goal of ASEAN, then, is to create, not to destroy. This, the Foreign Minister of Thailand, Thanat Khoman, stressed when it was his turn to speak. At a time when the Vietnam conflict was raging and American forces seemed forever entrenched in Indochina, he had foreseen their eventual withdrawal from the area and had accordingly applied himself to adjusting Thailand’s foreign policy to a reality that would only become apparent more than half a decade later. He must have had that in mind when, on that occasion, he said that the countries of Southeast Asia had no choice but to adjust to the exigencies of the time, to move toward closer cooperation and even integration. Elaborating on ASEAN objectives, he spoke of “building a new society that will be responsive to the needs of our time and efficiently equipped to bring about, for the enjoyment and the material as well as spiritual advancement of our peoples, conditions of stability and progress. Particularly what millions of men and women in our part of the world want is to erase the old and obsolete concept of domination and subjection of the past and replace it with the new spirit of give and take, of equality and partnership. More than anything else, they want to be master of their own house and to enjoy the inherent right to decide their own destiny …” While the nations of Southeast Asia prevent attempts to deprive them of their freedom and sovereignty, he said, they must first free themselves from the material impediments of ignorance, disease and hunger. Each of these nations cannot accomplish that alone, but by joining together and cooperating with those who have the same aspirations, these objectives become easier to attain. Then Thanat Khoman concluded: “What we have decided today is only a small beginning of what we hope will be a long and continuous sequence of accomplishments of which we ourselves, those who will join us later and the generations to come, can be proud. Let it be for Southeast Asia, a potentially rich region, rich in history, in spiritual as well as material resources and indeed for the whole ancient continent of Asia, the light of happiness and well-being that will shine over the uncounted millions of our struggling peoples.” The Foreign Minister of Thailand closed the inaugural session of the Association of Southeast Asian Nations by presenting each of his colleagues with a memento. Inscribed on the memento presented to the Foreign Minister of Indonesia, was the citation, “In recognition of services rendered by His Excellency Adam Malik to the ASEAN organization, the name of which was suggested by him.” And that was how ASEAN was conceived, given a name, and born. It had been barely 14 months since Thanat Khoman brought up the ASEAN idea in his conversations with his Malaysian and Indonesian colleagues. In about three more weeks, Indonesia would fully restore diplomatic relations with Malaysia, and soon after that with Singapore. That was by no means the end to intra-ASEAN disputes, for soon the Philippines and Malaysia would have a falling out on the issue of sovereignty over Sabah. Many disputes between ASEAN countries persist to this day. But all Member Countries are deeply committed to resolving their differences through peaceful means and in the spirit of mutual accommodation. Every dispute would have its proper season but it would not be allowed to get in the way of the task at hand. And at that time, the essential task was to lay the framework of regional dialogue and cooperation. The two-page Bangkok Declaration not only contains the rationale for the establishment of ASEAN and its specific objectives. It represents the organization’s modus operandi of building on small steps, voluntary, and informal arrangements towards more binding and institutionalized agreements. All the founding member states and the newer members have stood fast to the spirit of the Bangkok Declaration. Over the years, ASEAN has progressively entered into several formal and legally-binding instruments, such as the 1976 Treaty of Amity and Cooperation in Southeast Asia and the 1995 Treaty on the Southeast Asia Nuclear Weapon-Free Zone. Against the backdrop of conflict in the then Indochina, the Founding Fathers had the foresight of building a community of and for all Southeast Asian states. Thus the Bangkok Declaration promulgated that “the Association is open for participation to all States in the Southeast Asian region subscribing to the aforementioned aims, principles and purposes.” ASEAN’s inclusive outlook has paved the way for community-building not only in Southeast Asia, but also in the broader Asia Pacific region where several other inter-governmental organizations now co-exist. The original ASEAN logo presented five brown sheaves of rice stalks, one for each founding member. Beneath the sheaves is the legend “ASEAN” in blue. These are set on a field of yellow encircled by a blue border. Brown stands for strength and stability, yellow for prosperity and blue for the spirit of cordiality in which ASEAN affairs are conducted. When ASEAN celebrated its 30th Anniversary in 1997, the sheaves on the logo had increased to ten – representing all ten countries of Southeast Asia and reflecting the colors of the flags of all of them. In a very real sense, ASEAN and Southeast Asia would then be one and the same, just as the Founding Fathers had envisioned. This article is based on the first chapter of ASEAN at 30, a publication of the Association of Southeast Asian Nations in commemoration of its 30th Anniversary on 8 August 1997, written by Jamil Maidan Flores and Jun Abad.

Ions Ions are charged substances that have formed through the gain or loss of electrons. Cations form from the loss of electrons and have a positive charge while anions form through the gain of electrons and have a negative charge. Cation Formation Cations are the positive ions formed by the loss of one or more electrons. The most commonly formed cations of the representative elements are those that involve the loss of all of the valence electrons. Consider the alkali metal sodium (Na) . It has one valence electron in the n=3 energy level. Upon losing that electron, the sodiu ion now has an octet of electrons from the second energy level and a charge of 1+ . The electron arrangement of the sodium ion is now the same as that of the noble gas neon. Consider a similar process with magnesium and aluminum. In this case, the magnesium atom loses its two valence electrons in order to achieve the same arrangement as the noble gas neon and a charge of 2+ . The aluminum atom loses its three valence electrons to have the same electron arrangement as neon and a charge of 3+ . For representative elements under typical conditions, three electrons is usually the maximum number that will be los. Representative elements will not lose electrons beyond their valence because they would have to "break" the octet of the previous energy level which provides stability to the ion. Anions Anions are the negative ions formed from the gain of one or more electrons. When nonmetal atoms gain elections, they often do so until their outermost principal energy level achieves an octet. For fluorine, which has an electron arrangement of (2, 7), it only needs to gain one electron to have the same electron arrangement as neon. Forming an octet (eight electrons in the outer shell) provides stability to the atom. Fluorine will gain one electron and have a charge of 1− . The electron arrangement of the fluoride ion (2, 8) will also change to reflect the gain of an electron. Oxygen has an electron arrangement of (2, 6) and needs to gain two electrons to fill the n=2 energy level and achieve an octet of electrons in the outermost shell. The oxide ion will have a charge of 2− as a result of gaining two electrons. Under typical conditions, three electrons is the maximum that will be gained in the formation of anions. Subatomic Particles in an Ion Since ions form from the gain or loss of electrons, we can also look at the number of subatomic particles (protons, neutrons, and electrons) found in an ion. Remember that the number of protons determines the identity of the element and will not change in a chemical process. Example 2.5.1 How many protons, neutrons, and electrons in a single oxide (O2−) ion? Solution Oxygen has the atomic number 8 so both the atom and the ion will have 8 protons. The average atomic mass of oxygen is 16. Therefore, there will be 8 neutrons (atomic mass−atomic number=neutrons) . A neutral oxygen atom would have 8 electrons. However, the anion has gained two electrons so O2− has 10 electrons. We can also use information about the subatomic particles to determine the identity of an ion. Example 2.5.2 An ion with a 2+ charge has 18 electrons. Determine the identity of the ion. Solution If an ion has a 2+ charge then it must have lost electrons to form the cation. If the ion has 18 electrons and the atom lost 2 to form the ion, then the neutral atom contained 20 electrons. Since it was neutral, it must also have had 20 protons. Therefore the element is calcium. Polyatomic Ions A polyatomic ion is an ion composed of two or more atoms that have a charge as a group (poly = many). The ammonium ion (see figure below) consists of one nitrogen atom and four hydrogen atoms. Together, they comprise a single ion with a 1+ charge and a formula of NH+4 . The hydroxide ion (see figure below) contains one hydrogen atom and one oxygen atom with an overall charge of 1− . The carbonate ion (see figure below) consists of one carbon atom and three oxygen atoms and carries an overall charge of 2− . The formula of the carbonate ion is CO2−3 . The atoms of a polyatomic ion are tightly bonded together and so the entire ion behaves as a single unit. The figures below show several examples. Soult Screenshot 2-2-1.png Figure 2.5.1 : The ammonium ion (NH+4) is a nitrogen atom (blue) bonded to four hydrogen atoms (white). Soult Screenshot 2-2-2.png Figure 2.5.2 : The hydroxide ion (OH−) is an oxygen atom (red) bonded to a hydrogen atom. Soult Screenshot 2-2-3.png Figure 2.5.3 : The carbonate ion (CO2−3) is a carbon atom (black) bonded to three oxygen atoms. The table below lists a number of polyatomic ions by name and by structure. The heading for each column indicates the charge on the polyatomic ions in that group. Note that the vast majority of the ions listed are anions - there are very few polyatomic cations. 1− 2− 3− 1+ Table 2.5.1 : Common Polyatomic Ions acetate, CH3COO− carbonate, CO2−3 arsenate, AsO3−3 ammonium, NH+4 bromate, BrO−3 chromate, CrO2−4 phosphite, PO3−3 chlorate, ClO−3 dichromate, Cr2O2−7 phosphate, PO3−4 chlorite, ClO−2 hydrogen phosphate, HPO2−4 cyanide, CN− oxalate, C2O2−4 dihydrogen phosphate, H2PO−4 peroxide, O2−2 hydrogen carbonate, HCO−3 silicate, SiO2−3 hydrogen sulfate, HSO−4 sulfate, SO2−4 hydrogen sulfide, HS− sulfite, SO2−3 hydroxide, OH− hypochlorite, ClO− nitrate, NO−3 nitrite, NO−2 perchlorate, ClO−4 permanganate, MnO−4 The vast majority of polyatomic ions are anions, many of which end in -ate or -ite. Notice that in some cases such as nitrate (NO−3) and nitrite (NO−2) , there are multiple anions that consist of the same two elements. In these cases, the difference between the ions is the number of oxygen atoms present, while the overall charge is the same. As a class, these are called oxyanions. When there are two oxyanions for a particular element, the one with the greater number of oxygen atoms gets the -ate suffix, while the one with the fewer number of oxygen atoms gets the -ite suffix. The four oxyanions of chlorine are shown below, which also includes the use of the prefixes hypo- and per-. ClO− , hypochlorite ClO−2 , chlorite ClO−3 , chlorate ClO−4 , perchlorate Not your usual ion Soult Screenshot 2-2-4.png "Drink you milk. It's good for your bones." We're told this from early childhood, and with good reason. Milk contains a good supply of calcium, part of the structure of bone. However, there are two other ionic components of hydroxyapatite, the mineral component. Phosphate ion and hydroxide ion make up the remainder of the inorganic material in bone. News You Can Use Bone is a very complex structure. It is composed of protein (mainly collagen), hydroxyapatite (a calcium-phosphate-hydroxide mixture), some other minerals, and contains 10 - 20% water. The calcium/phosphate ratios are not stoichiometric, but vary somewhat from one portion of bone to the next. Bones are very strong but will break under enough stress. Regular exercise and proper nutrition help to increase bone strength. Watch a video about bone structure at http://www.youtube.com/watch?v=d9owEvYdouk Nitrate is an anion with a complex bonding structure. Major sources for this ion in drinking water are runoff from fertilizer, septic tank leakage, sewage, and natural deposits. High concentrations of nitrates represent a significant health hazard, especially to infants. The nitrate in the body is converted to nitrite, which then binds to hemoglobin. This binding decreases the ability of hemoglobin to transport oxygen, thus depriving the cells of the O2 needed for proper functioning. Cyanide production is widespread throughout nature. Forest fires will produce significant amounts of cyanide. Many plants contain cyanide, and it is produced by a number of bacteria, algae, and fungi. Cyanide is used industrially in metal finishing, iron and steel mills, and in organic synthesis processes. This material is also an important component for the refining of precious metals. Formation of a complex between cyanide and gold allows extraction of this metal from a mixture.

Covalent Molecules and Compounds Just as an atom is the simplest unit that has the fundamental chemical properties of an element, a molecule is the simplest unit that has the fundamental chemical properties of a covalent compound. Some pure elements exist as covalent molecules. Hydrogen, nitrogen, oxygen, and the halogens occur naturally as the diatomic (“two atoms”) molecules H2, N2, O2, F2, Cl2, Br2, and I2 (part (a) in Figure 3.1.1). Similarly, a few pure elements exist as polyatomic (“many atoms”) molecules, such as elemental phosphorus and sulfur, which occur as P4 and S8 (part (b) in Figure 3.1.1). Each covalent compound is represented by a molecular formula, which gives the atomic symbol for each component element, in a prescribed order, accompanied by a subscript indicating the number of atoms of that element in the molecule. The subscript is written only if the number of atoms is greater than 1. For example, water, with two hydrogen atoms and one oxygen atom per molecule, is written as H2O. Similarly, carbon dioxide, which contains one carbon atom and two oxygen atoms in each molecule, is written as CO2. Covalent compounds that predominantly contain carbon and hydrogen are called organic compounds. The convention for representing the formulas of organic compounds is to write carbon first, followed by hydrogen and then any other elements in alphabetical order (e.g., CH4O is methyl alcohol, a fuel). Compounds that consist primarily of elements other than carbon and hydrogen are called inorganic compounds; they include both covalent and ionic compounds. In inorganic compounds, the component elements are listed beginning with the one farthest to the left in the periodic table, as in CO2 or SF6. Those in the same group are listed beginning with the lower element and working up, as in ClF. By convention, however, when an inorganic compound contains both hydrogen and an element from groups 13–15, hydrogen is usually listed last in the formula. Examples are ammonia (NH3) and silane (SiH4). Compounds such as water, whose compositions were established long before this convention was adopted, are always written with hydrogen first: Water is always written as H2O, not OH2. The conventions for inorganic acids, such as hydrochloric acid (HCl) and sulfuric acid (H2SO4), are described elswhere. Note! For organic compounds: write C first, then H, and then the other elements in alphabetical order. For molecular inorganic compounds: start with the element at far left in the periodic table; list elements in same group beginning with the lower element and working up. Write the molecular formula of each compound. a. The phosphorus-sulfur compound that is responsible for the ignition of so-called strike anywhere matches has 4 phosphorus atoms and 3 sulfur atoms per molecule. b. Ethyl alcohol, the alcohol of alcoholic beverages, has 1 oxygen atom, 2 carbon atoms, and 6 hydrogen atoms per molecule. c. Freon-11, once widely used in automobile air conditioners and implicated in damage to the ozone layer, has 1 carbon atom, 3 chlorine atoms, and 1 fluorine atom per molecule. Solution: a. • A The molecule has 4 phosphorus atoms and 3 sulfur atoms. Because the compound does not contain mostly carbon and hydrogen, it is inorganic. • B Phosphorus is in group 15, and sulfur is in group 16. Because phosphorus is to the left of sulfur, it is written first. • C Writing the number of each kind of atom as a right-hand subscript gives P4S3 as the molecular formula. b. • A Ethyl alcohol contains predominantly carbon and hydrogen, so it is an organic compound. • B The formula for an organic compound is written with the number of carbon atoms first, the number of hydrogen atoms next, and the other atoms in alphabetical order: CHO. • C Adding subscripts gives the molecular formula C2H6O. c. • A Freon-11 contains carbon, chlorine, and fluorine. It can be viewed as either an inorganic compound or an organic compound (in which fluorine has replaced hydrogen). The formula for Freon-11 can therefore be written using either of the two conventions. • B According to the convention for inorganic compounds, carbon is written first because it is farther left in the periodic table. Fluorine and chlorine are in the same group, so they are listed beginning with the lower element and working up: CClF. Adding subscripts gives the molecular formula CCl3F. • C We obtain the same formula for Freon-11 using the convention for organic compounds. The number of carbon atoms is written first, followed by the number of hydrogen atoms (zero) and then the other elements in alphabetical order, also giving CCl3F. Write the molecular formula for each compound. a. Nitrous oxide, also called “laughing gas,” has 2 nitrogen atoms and 1 oxygen atom per molecule. Nitrous oxide is used as a mild anesthetic for minor surgery and as the propellant in cans of whipped cream. b. Sucrose, also known as cane sugar, has 12 carbon atoms, 11 oxygen atoms, and 22 hydrogen atoms. c. Sulfur hexafluoride, a gas used to pressurize “unpressurized” tennis balls and as a coolant in nuclear reactors, has 6 fluorine atoms and 1 sulfur atom per molecule. Answer: a. N2O b. C12H22O11 c. SF6. Ionic Compounds The substances described in the preceding discussion are composed of molecules that are electrically neutral; that is, the number of positively-charged protons in the nucleus is equal to the number of negatively-charged electrons. In contrast, ions are atoms or assemblies of atoms that have a net electrical charge. Ions that contain fewer electrons than protons have a net positive charge and are called cations. Conversely, ions that contain more electrons than protons have a net negative charge and are called anions. Ionic compounds contain both cations and anions in a ratio that results in no net electrical charge. Note! Ionic compounds contain both cations and anions in a ratio that results in zero electrical charge.An ionic compound that contains only two elements, one present as a cation and one as an anion, is called a binary ionic compound. One example is MgCl2, a coagulant used in the preparation of tofu from soybeans. For binary ionic compounds, the subscripts in the empirical formula can also be obtained by crossing charges: use the absolute value of the charge on one ion as the subscript for the other ion. This method is shown schematically as follows: Crossing charges. One method for obtaining subscripts in the empirical formula is by crossing charges. When crossing charges, it is sometimes necessary to reduce the subscripts to their simplest ratio to write the empirical formula. Consider, for example, the compound formed by Mg2+ and O2−. Using the absolute values of the charges on the ions as subscripts gives the formula Mg2O2:Polyatomic Ions Polyatomic ions are groups of atoms that bear net electrical charges, although the atoms in a polyatomic ion are held together by the same covalent bonds that hold atoms together in molecules. Just as there are many more kinds of molecules than simple elements, there are many more kinds of polyatomic ions than monatomic ions. Two examples of polyatomic cations are the ammonium (NH4+) and the methylammonium (CH3NH3+) ions. P. The method used to predict the empirical formulas for ionic compounds that contain monatomic ions can also be used for compounds that contain polyatomic ions. The overall charge on the cations must balance the overall charge on the anions in the formula unit. Thus, K+ and NO3− ions combine in a 1:1 ratio to form KNO3 (potassium nitrate or saltpeter), a major ingredient in black gunpowder. Similarly, Ca2+ and SO42− form CaSO4 (calcium sulfate), which combines with varying amounts of water to form gypsum and plaster of Paris. The polyatomic ions NH4+ and NO3− form NH4NO3 (ammonium nitrate), a widely used fertilizer and, in the wrong hands, an explosive. One example of a compound in which the ions have charges of different magnitudes is calcium phosphate, which is composed of Ca2+ and PO43− ions; it is a major component of bones. The compound is electrically neutral because the ions combine in a ratio of three Ca2+ ions [3(+2) = +6] for every two ions [2(−3) = −6], giving an empirical formula of Ca3(PO4)2; the parentheses around PO4 in the empirical formula indicate that it is a polyatomic ion. Writing the formula for calcium phosphate as Ca3P2O8 gives the correct number of each atom in the formula unit, but it obscures the fact that the compound contains readily identifiable PO43− ions.Summary • There are two fundamentally different kinds of chemical bonds (covalent and ionic) that cause substances to have very different properties. • The composition of a compound is represented by an empirical or molecular formula, each consisting of at least one formula unit.Contributors The atoms in chemical compounds are held together by attractive electrostatic interactions known as chemical bonds. Ionic compounds contain positively and negatively charged ions in a ratio that results in an overall charge of zero. The ions are held together in a regular spatial arrangement by electrostatic forces. Most covalent compounds consist of molecules, groups of atoms in which one or more pairs of electrons are shared by at least two atoms to form a covalent bond. The atoms in molecules are held together by the electrostatic attraction between the positively charged nuclei of the bonded atoms and the negatively charged electrons shared by the nuclei. The molecular formula of a covalent compound gives the types and numbers of atoms present. Compounds that contain predominantly carbon and hydrogen are called organic compounds, whereas compounds that consist primarily of elements other than carbon and hydrogen are inorganic compounds. Diatomic molecules contain two atoms, and polyatomic molecules contain more than two. A structural formula indicates the composition and approximate structure and shape of a molecule. Single bonds, double bonds, and triple bonds are covalent bonds in which one, two, and three pairs of electrons, respectively, are shared between two bonded atoms. Atoms or groups of atoms that possess a net electrical charge are called ions; they can have either a positive charge (cations) or a negative charge (anions). Ions can consist of one atom (monatomic ions) or several (polyatomic ions). The charges on monatomic ions of most main group elements can be predicted from the location of the element in the periodic table. Ionic compounds usually form hard crystalline solids with high melting points. Covalent molecular compounds, in contrast, consist of discrete molecules held together by weak intermolecular forces and can be gases, liquids, or solids at room temperature and pressure. An empirical formula gives the relative numbers of atoms of the elements in a compound, reduced to the lowest whole numbers. The formula unit is the absolute grouping represented by the empirical formula of a compound, either ionic or covalent. Empirical formulas are particularly useful for describing the composition of ionic compounds, which do not contain readily identifiable molecules. Some ionic compounds occur as hydrates, which contain specific ratios of loosely bound water molecules called waters of hydration.

Personal cleanliness means attending to your personal hygiene regularly, thus keeping your body free from bad odor and infectious diseases. In keeping your body clean, you have to use grooming aids discussed in previous module. Remember that to achieve a clean and healthy body you need to practice good grooming habits as well as good healthy habits. Your Body Regular care of the body is necessary for good health and pleasing appearance. As you grow, you should learn to be responsible to your self. You should never neglect your body. Your body is the temple of the Holy Spirit. That is why , if you take good care of your body, you are in effect taking care of the place where the Holy Spirit resides. You are the “masterpiece of God’s creation” which means to say that you are above all other creations of God. So, it is best to maintain your body clean and healthy. For your own good and in so doing, you are showing your reverence to God, our creator. “Rule of Thumb” to keep your body clean is to take a regular bath. Taking a bath is necessary to remove dust, germs, as well as dirt accumulated from your daily activities. It is invigorating for the act of cleansing stimulates blood circulation. It will give your skin a healthy pinkish glow. Something to read: Home Economics and Livelihood Education 7 Seibo College 31 There are three ways of taking a bath: 1. Full bath It includes washing, shampooing the hair, soaping the whole body and rinsing with clear water. It is a thorough cleansing of the body. 2. Shower A shower bath usually takes a shorter time than full bath. A wash clothe or sponge with thick lather is rub all over the body starting from the navel, then the thigh, joints, armpits, and the rest of the body. Then rinse your body in the shower and pat your body dry with clean towel 3. Sponge bath Use wash cloth or face towel with soap, soak in warm or cold water. Rub it briskly over the body. Rinse the cloth with clean water then use it to remove soap from the body. A sponge bath is usually given to a sick person.

LESSON 2 Early Theories on the Origin of Life • Identify the different theories on the origin of life. • Describe each theory and determine their differences What are the characteristics of living things? Before learning about the history of Earth based on geological evidence, early scientists explored the possibilities of how the first life-form existed. There are several theories about the origin of life. Theory of Catastrophism The theory of catastrophism supported by French scientists Georges Cuvier (1769-1832) and Alcide Dessalines d'Orbigny (1802-1857), is said to be a modification of the creation story of the Bible. It states that there have been several living creations from God, each encountered a catastrophe that completely destroyed them. Each new creation consisted of new life-forms, which happen to be different from the previous ones. Theory of Abiogenesis The theory of abiogenesis, or the spontaneous generation theory, states that living things were naturally created from nonliving things such as simple organic compounds. The theory supposes that abiogenesis occurred between 3.8 and 4 Gya. The experiment performed by Stanley Miller in 1953 gave way to many speculations and studies on how life on Earth really began. His research involved a simulation of the possible environment on Earth in the past. He demonstrated how an electric spark (which is a simulation for lightning) when passed through simple organic gases (similar to the early Earth atmosphere), resulted in the formation of amino acids, which are now known as the building blocks of proteins and the components of living tissues. Theory of Biogenesis The theory of biogenesis presented a strong argument against abiogenesis. This theory states that living things come from living things. Experiments of Francesco Redi and Louis Pasteur disproved the thought of spontaneous generation during their time (figure 5-1). Louis Pasteur argued that life comes from preexisting life and not from nonliving material. However, it should be noted that the "abiogenesis" or "spontaneous generation" that he opposed referred to any modern, existing, fully-formed organisms, not the original generation of life. Louis Pasteur's law of biogenesis contradicted the common belief during his time that cattle dung gives rise to flies, or old clothes with rotten food gives rise to mice. The idea of spontaneous generation was popular until near the seventeenth century. Even famous scientists of that period, such as Descartes, Galileo, and Jan Baptista van Helmont, believed in this theory. CIENCE PIONEER Francesco Redi (1626-1697). Francesco Redi is a physician, a naturalist, and a poet. His works challenged the popular theory of spontaneous generation. He disproved the idea that living things may arise from nonliving things. He also worked on toxicology using viper's venom. He discovered and worked on some parasites that caused disease in humans. SCIENCE CAREER Evolutionary Biologist An evolutionary biologist studies the descent of species and the origin of new species of living things. Working as evolutionary biologist means studying and researching species diversity, their interaction with the environment, their adaptation to change, their ancestors, and their possible origins. This career is important in the field of science because it seeks an answer to the questions about how life began on Earth.

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