1st Quarter Summary (PDF)

ORIGIN OF THE UNIVERSE UNIVERSE – comprise all space and time, and all matter & energy. 13.8 billion Years Old 4.6% Baryonic Matter - “ordinary” matter consisting of protons, electrons, and neutrons: atoms, planets, stars, galaxies, nebulae, and o...

ORIGIN OF THE UNIVERSE UNIVERSE – comprise all space and time, and all matter & energy. 13.8 billion Years Old 4.6% Baryonic Matter - “ordinary” matter consisting of protons, electrons, and neutrons: atoms, planets, stars, galaxies, nebulae, and other bodies 24% Cold Dark Matter - matter that has gravity but does not emit light. 71.4% Dark Energy – a source of anti-gravity; a force that counteracts gravity and causes the universe to expand. Hydrogen, Helium & Lithium – three most abundant elements. Non-scientific Thought/ Divine Theory/ Creationism Theory o Ancient Egyptians believed in many gods and myths which narrate that the world arose from an infinite sea at the first rising of the sun. o The Kuba people of Central Africa tell the story of a creator god Mbombo (or Bumba) who, alone in a dark and water-covered Earth, felt an intense stomach pain and then vomited the stars, sun, and moon. o In India, there is the narrative that gods sacrificed Purusha, the primal man whose head, feet, eyes, and mind became the sky, earth, sun, and moon respectively. o The monotheistic religions of Judaism, Christianity, and Islam claim that a supreme being created the universe, including man and other living organisms. NOTE: Unlike hypotheses in the sciences, religious beliefs cannot be subjected to tests using the scientific method. For this reason, they cannot be considered valid topic of scientific inquiry. Steady State Theory o Proposed in 1948 by Bondi and Gould and by Hoyle, stated that new matter is created as the universe expands thereby maintaining its density. o Falsified by the discovery of Cosmic Microwave Background Radiation. Oscillating / Pulsating Universe o In this theory it is assumed that there is continuous expansion and contraction in universe. It proposes that the universe will keep expanding more and more then slowly it stop. Then it will start to contract due to gravitation. This contraction will continue until the universe become more compact and will later explode and expand again. Big Bang Theory o Currently accepted theory of the origin and evolution of the universe, postulates that 13.8 billion years ago, the universe expanded from a tiny dense and hot mass to its present size and much cooler state. Evidence under Big Bang Theory. ▪ Expanding Theory ❖ RedShift – evidence for expanding universe. The positions of the spectral lines for helium for light coming from the sun are shifted towards the red end of the spectrum. ❖ Doppler Effect – similar to redshift. It uses soundwaves; to a stationary observer, the frequency or pitch of a receding source decreases as it moves away. ❖ Cosmic Microwave Background Radiation (CMBR) – a strikingly uniform faint glow in the microwave band coming from all directions-blackbody radiation with an average temperature of about 2.7 degrees above absolute zero. NOTE: The “bang” should not be taken as an explosion; it is better thought of a simultaneous appearance of space everywhere. The theory does not identify the cause of the “bang.” ORIGIN OF THE SOLAR SYSTEM SOLAR SYSTEM – a part of the vast universe. Located somewhere in Milky Way Galaxy. Consists of the sun being the center, inner planets or terrestrial or rocky planets (Mercury, Venus, Earth, & Mars), outer planets or Jovian or Gas Giants (Jupiter, Saturn, Uranus, & Neptune) and other celestial bodies such as satellites, comets, asteroids, and meteoroids. Based on recent data, existing for about 4.6 billion years. There are major theories that explain the origin of the solar system. o Nebular Hypothesis Theory - the sun and other celestial bodies orbiting around it were formed from a nebula- a spinning cloud of gases. These clouds are gravitationally unstable, and matter coalesces within them to smaller denser clumps, which then rotate, collapse, and form stars. o Encounter Theory or Sun-Star Theory – a sun passing and encountering the sun draws sun matter that would condense to planets. o Protoplanetary Hypothesis – Current Hypothesis – modified explanation of Nebular Hypothesis. VENUS, EARTH, & MARS Similarities and Differences Venus, Earth, and Mars are part of the inner terrestrial or "rocky" planets. Their composition and densities are not too different from each other. Venus is considered to be the Earth's twin planet. It has a very similar size and mass with the Earth. Mars is about half the Earth's size. Orbital period and velocity are related to the planet's distance from the sun. Among the three planets, Venus is the nearest and Mars is the farthest from the Sun. Rotational speed of Earth and Mars are very similar. Rotational speed of Venus is extremely slow. Abundance of liquid water on Earth, hence the blue color. The Earth is a habitable planet. CHARACTERISTICS OF EARTH THAT ARE NECESSARY TO SUSTAIN LIFE What makes Earth Habitable? LOCATION – the zone where Earth is located at, is what we called Goldilocks Zone or Habitable Zone. It summarizes the characteristics of Earth that makes it habitable. TEMPERATURE - Life seems to be limited to a temperature range of -15°C to 115°C. In this range, liquid water can still exist under certain conditions. Not enough and Too much Factor o Low temperatures cause chemicals to react slowly, which interferes with the reactions necessary for life. It can also cause the freezing of water, making liquid water unavailable. o At about 125°C, protein and carbohydrate molecules, and the genetic material (ex. DNA & RNA) start to break apart. Also, high temperatures cause the quick evaporation of water. ATMOSPHERE – Earth has the right size to hold a sufficient-sized atmosphere. Earth’s atmosphere is about 100 miles thick. It keeps the surface warm & protects it from radiation & small to medium sized meteorites. Not enough and Too much Factor o Small planets and moon have insufficient gravity to hold an atmosphere. The gas molecules escape to space, leaving the planet or moon without an insulating blanket or a proactive shield. o Venus’s is 100 times thicker than Earth’s. It is made almost entirely of greenhouse gasses, making the surface too hot for life. The four giant planets are completely made of gas.  WATER – in its liquid form, is one of the most important prerequisites for life as we know it. The fact that the human body has water that composed it. Not enough and Too much Factor o There is recent evidence that water, in the form of brine (salty water) flows intermittently on the surface of Mars. Makes it uninhabitable. ENERGY – with a steady input of either light (sun) or chemical energy (from chemical reaction, often in the form of heat), cells can run the chemical reactions necessary for life. Not enough and Too much Factor o when there is too little sunlight or too few of the chemicals that provide energy to cells, such as iron or sulfur, organisms die. o Light energy is a problem if it makes a planet too hot or if there are too many harmful rays, such as ultraviolet. Too many energy-rich chemicals are not a problem. NUTRIENTS – used to build and maintain an organism’s body. All solid planets & moons have the same general chemical makeup, so nutrients are present. Those with a water cycle or volcanic activity can transport and replenish the chemicals required for living organisms. Not enough and Too much Factor o Without chemicals to make proteins & carbohydrates, organisms cannot grow. Planets without systems to deliver nutrients to its organisms (ex. Water cycle or volcanic activity) cannot support life. Also, when nutrients are spread so thin that they are hard to obtain, such as on a gas planet, life cannot exist. o Too many nutrients are not a problem. However, too active circulation system, such as volcanism on Jupiter’s moon, the churning atmospheres of the gas planets, interferes with an organism’s ability to get enough nutrients. EARTH AND EARTH SUBSYSTEMS - Earth system is essentially a closed system. It receives energy from the sun and returns some of this energy to space. - A closed system is a system in which there is only an exchange of heat or energy and no exchange of matter. There are 4 subsystems of the Earth: 1. ATMOSPHERE – is the thin gaseous layer that envelopes the Earth and pulled by the gravitational force of the Earth. o It is composed of 78% Nitrogen, 21% Oxygen 1% Argon, Carbon dioxide, Carbon Monoxide, Helium, Ozone, Hydrogen and other trace amount of other gases. o One of the most important processes by which the heat on the Earth's surface is redistributed is through atmospheric circulation. o There is also a constant exchange of heat and moisture between the atmosphere and the hydrosphere through the hydrologic cycle. Earth’s Atmosphere is made up of different layers: ▪ TROPOSPHERE – Air is closest to the Earth, where we live, where weather is formed, airplanes fly at the top of it. (10miles (16km) above the Earth's surface) ▪ STATROSPHERE – Ozone layer is part of it (helps shield the Earth from harmful sun rays). (30miles (48km) above the Earth's surface) ▪ MESOSPHERE – Coldest layer, meteorites break apart here. (50miles (80km) above the Earth's surface) ▪ THERMOSPHERE – Five times as deep as all other layers combined, very hot (up to 2000°C). (300miles (483km) above the Earth's surface) ▪ EXOSPHERE – Satellites circle the Earth here, fades into space. (Beyond 300miles above the Earth’s surface) 2. GEOSPHERE - describes all of the rocks, minerals and ground that are found on and in Earth. This includes all of the mountains on the surface, as well as all of the liquid rock in the mantle below us and the minerals and metals of the outer and inner cores.  The continents, the ocean floor, all of the rocks on the surface, and all of the sand in the deserts are all considered part of the geosphere. Basically, if it looks like solid ground, it's part of the 'ground' sphere. 3. HYDROSPHERE - Planet Earth has been called the "Blue Planet" due to the abundant water on its surface Over 70 percent of the surface area of the earth is covered by water. All the earth’s water, solid or in liquid form, those that are contained in glaciers, rocks, soil, and the air, comprise the earth’s hydrosphere. SOURCES OF WATER ❖ Ocean - A big portion of earth’s water is found in ocean. The oceans cover more than 70% of the Earth's surface and contain 97% of the Earth's water. If the ocean's total salt content were dried, it would cover the continents to a depth of 5 feet. Together with the atmosphere, oceans regulate global temperatures, shape weather and climate patterns, and cycle elements through the biosphere. ❖ Inland Waters - Household, commercial and agricultural water supply mainly come from inland bodies of water. Two major inland waters are described below. 1. Rivers - A volume of a fresh flowing water across the surface of the land usually to the sea. Rivers flow in channels. 2. Lakes - A reservoir of relatively still water that is surrounded by land. It is formed from the accumulation of large amounts of water in natural or artificial depressions on the surface of the land. Other inland waters include ponds, spring, stream, wetlands, floodplains and reservoirs. ❖ Groundwater - It is the water found underground in the cracks and spaces in soil, sand and rock. It is stored in and moves slowly through geologic formations of soil, sand and rocks called aquifers. Groundwater supplies drinking water, used for irrigation to grow crops and an important component in many industrial processes. ❖ Massive Body of Ice - About 2 percent of earth’s waters is in a form of solid, a massive body of ice called glaciers. Deposited snow that falls during winter season piles up yearly. This accumulated snow transforms the lower layers into solid ice. THE HYDROLOGIC CYCLE (WATER CYCLE Water on earth is continuously moving. It endlessly circulating through the hydro- logic cycle. As water goes in a cycle, it changes its states. From liquid to ice to gas and back again. 4. BIOSPHERE - is where all forms of life exist. Since life exist in the air, in water and on the ground, its boundaries overlap other “sphere” because life can be found everywhere on earth. The biosphere is sometimes thought of as one large ecosystem — a complex community of living and nonliving things functioning as a single unit. MINERALS AND ROCKS MINERALS – naturally occurring, inorganic, with solid orderly crystalline structure and has definite chemical composition. - basic building blocks of rocks. Geosphere Physical Properties 1. Luster – it is the quality and intensity of reflected light exhibited by the mineral. a. Metallic – generally opaque and exhibit a resplendent shine similar to a polished metal. b. Non-metallic – vitreous (glassy), adamantine (brilliant/diamond-like), resinous, silky, pearly, dull (earthy), greasy, etc. 2. Hardness – it is a measure of the resistance of a mineral (not specifically surface) to abrasion. Hardness scale designed by German geologist/mineralogist Friedrich Mohs in 1812 (Mohs Scale of Hardness). The test compares the resistance of a mineral relative to the 10 reference minerals with known hardness. It is simply determining the hardness of a mineral by scratching them with common objects of known hardness (e.g. copper coin -3.0-3.5). 3. Color – it indicates the mineral’s color appearance. 4. Streak – it is the color of a mineral in powdered form. 5. Crystal Form - The external shape of a crystal or groups of crystals is displayed / observed as these crystals grow in open spaces. The form reflects the supposedly internal structure (of atoms and ions) of the crystal (mineral). It is the natural shape of the mineral before the development of any cleavage or fracture. Examples include prismatic, tabular, bladed, platy, reniform and equant. A mineral that do not have a crystal structure is described as amorphous. 6. Cleavage – It is the property of some minerals to break along parallel repetitive planes of weakness to form smooth, flat surfaces. When minerals break evenly in more than one direction, cleavage is described by the number of cleavage directions and the angle(s) between planes (e.g., cleavage in 2 directions at 90 degrees to each other). 7. Fracture – Some minerals may not have cleavages but exhibit broken surfaces that are irregular and non-planar. Quartz for example has an inherent weakness in the crystal structure that is not planar. Examples of fracture are conchoidal, fibrous, hackly, and uneven among others. 8. Specific Gravity – It is the ratio of the weight of a mineral to the weight of an equal volume of water. A bucket of silver (SG 10) would weigh 10 times more than a bucket of water (SG 1). It is a measure to express the density (mass per unit volume) of a mineral. The specific gravity of a mineral is numerically equal to density.  9. Others – There are certain unique properties of minerals that actually help in their identification (e.g. magnetism, odor, taste, tenacity, reaction to acid, etc.). Magnetite is strongly magnetic; sulfur has distinctive smell; halite is salty; calcite fizzes with acid as with dolomite but in powdered form. Chemical Properties Mineral Groups - A more stable and less ambiguous basis for classification of minerals is by chemical composition. 1. Silicates – minerals containing 2 of the most abundant elements in the Earth’s crust, namely, silicon and oxygen. When linked together, these two elements form the silicon oxygen tetrahedron - the fundamental building block of silicate minerals. Over 90% of the rock-forming minerals belong to this group. Aside from Si (46.6 % by wt.) and O (27.7%), the other most common elements that make the earth’s crust are Al (8.1), Fe (5.0), Ca (3.6), Mg (3.1), Na (2.8) and K 2.6). 2. Oxides – minerals containing Oxygen anion (O2 - ) combined with one or more metal ions 3. Sulfates – minerals containing Sulfur and Oxygen anion (SO4) - combined with other ions 4. Sulfides – minerals containing sulfur anion (S2) - combined with one or more ions. Some sulfides are sources of economically important metals such as copper, lead and zinc. 5. Carbonates – minerals containing the carbonate anion (CO3) 2- combined with other elements 6. Native Elements – minerals that form as individual elements. a. Metals and Inter-metals – minerals with high thermal and electrical conductivity, typically with metallic luster, low hardness (gold, lead) b. Semi-metals – minerals that are more fragile than metals and have lower conductivity (arsenic, bismuth) c. Nonmetals – nonconductive (sulfur, diamond) 7. Halides – minerals containing halogen elements combined with one or more elements. CLASSIFICATION OF ROCKS Generally, rocks are classified on the basis of the mode of formation and that some of these physical and chemical properties are inherent on how the rocks are formed. There are three types of rocks, IGNEOUS, SEDIMENTARY & METAMORPHIC ROCKS 1. IGNEOUS ROCKS – formed through the solidification and cooling/crystallization of molten material (magma or lava). Rate of cooling is one of the most important factors that control the crystal size of this rock. TYPES OF IGNEOUS ROCK a. Plutonic/Intrusive Igneous Rock - the slow cooling occurs underground resulting for large interlocking crystals, a texture called Phaneritic. o Phaneritic Texture (coarse-grained): granite, diorite, gabbro b. Volcanic/Extrusive Igneous Rock - from solidified lava at or near the surface of the earth; fast rate of cooling/crystallization due to huge variance in the temperature between Earth’s surface and underneath; common textures: aphanitic, porphyritic, and vesicular. o Aphanitic Texture (fine-grained) – minerals not visible to the naked eye. Ex. Andesite o Porphyritic Texture (two-distinct grain sizes) – Ex. Rhyolite o Vesicular Texture – voids created by rapid cooling which causes air bubbles to be trapped inside. Ex. Basalt Igneous rocks are also classified according to silica content: felsic, intermediate, mafic and ultramafic. - felsic: also called granitic; >65% silica, generally light-colored - intermediate: also called andesitic; 55-65% silica; generally medium colored (medium gray) - mafic: also called basaltic; 45-55% silica; generally dark colored - ultramafic: 1cm is called bedding and < 1cm is called lamination): layering is the result of a change in grain size and composition; each layer represents a distinct period of deposition. ▪ Sedimentary rocks are either CLASTIC or NON-CLASTIC. o CLASTIC/ TERIIGENOUS - form from the accumulation and lithification of sediments derived from the breakdown of pre-existing rocks. They are further classified according to dominant grain size. o NON-CLASTIC/BIOCHEMICAL/CHEMICAL - derived from sediments that precipitated from concentrated solutions (e.g. seawater) or from the accumulation of biologic or organic material (e.g. shells, plant material). They are further classified on the basis of chemical composition. 3. METAMORPHIC ROCKS - rocks that form from the transformation of pre-existing rocks (igneous, sedimentary, or metamorphic rocks) through the process of metamorphism. Metamorphism can involve changes in the physical and chemical properties of rocks in response to heat, pressure, and chemically active fluids. They are commonly formed underneath the earth through metamorphism. - TYPES OF METAMORPHISM o CONTACT METAMORPHISM - Heat as the main factor: occurs when a pre-existing rocks get in contact with a heat source (magma) - Occurs on a relatively small scale: around the vicinity of intruding magma - Creates non-foliated metamorphic rocks (e.g. hornfels) o REGIONAL METAMORPHISM - Pressure as main factor: occurs in areas that have undergone deformation during orogenic event resulting in mountain belts - Occurs in a regional/large scale - Creates foliated metamorphic rocks such as schist and gneiss - Non-foliated rocks like marble also form thru regional metamorphism, where pressure is not intense, far from the main geologic event THE ROCKS OF EARTH'S CRUST ARE CONSTANTLY BEING RECYCLED AND CHANGED INTO NEW FORMS THROUGH GEOLOGIC PROCESSES. THIS CONTINUAL TRANSFORMATION OF ROCKS FROM ONE TYPE TO ANOTHER IS CALLED THE ROCK CYCLE. - Rock can be changed through the processes of weathering, heating, melting, cooling, and compaction. Any one rock type can be changed into a different rock type as its chemical composition and physical characteristics are transformed. The minerals and metals found in rocks have been essential to human civilization.