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Reporters: Ace B. Correos Gerone P. Ricardo Jethru Ray A. Canoy Demie Xyza F. Rendon A Review of Matter Is a substance of which all objects are made. An object’s resistance to a change in its state of motion. A Review of Matter Mass is a measure of inertia. Is a source of gravitation Weight is the term used in science and technology for the gravitational force between planet or any other large object and relatively small objects. Matter can be changed into energy and energy into matter. Structure of Matter Matter has structure at many levels, from groupings of galaxies so vast that light rays take hundreds of million years to cross them to particles so small that scientists describe them as point-like. Structure of Matter An atom is made up of particles called protons, electrons and neutrons. Proton- a positively charged elementary particle that is a fundamental constituent of all atomic nuclei. - it is the lightest baryon Structure of Matter Neutron- an elementary particle having no charge. - its mass is slightly greater than that of a proton Electron- an elementary particle that is a fundamental constituent of matter -it is the component outside the nucleus of an atom. Structure of Matter Protons and neutrons, which carry most of the atom’s mass, are composed of point like units known as quarks. Particles smaller than an atom is called subatomic particles. The diameter of an atom ranges from about 0.1 to 0.5 nanometre. Nanometre- is a billionth of a meter or is 1 25,400,00 inches The General States of Matter Matter can change from one state to another. The General States of Matter Solids tend to retain their shape, and they resist compression (reduction in the amount of space they occupy) Liquids assume the shape their container and can flow freely. Like solids they also resist compression. The atoms or molecules of a liquid are in contact with one another but are not linked, so they can move freely. The General States of Matter Gases expand to fill their containers, and the can be compressed fairly easily. The atoms or molecules of a gas are not in contact with one another and are always moving violently. The Physicists’ Other States of Matter Plasma Superconductor Superfluid Bose-Einstein condensate The Physicists’ Other States of Matter Plasma are gas-like substances in which some or all atoms have lost at least on electron, leaving a mixture of free electrons and positively charged ions. Plasmas form at temperatures of tens of thousands of degrees or higher, or through the action of an electric current. On earth, plasmas are found in lightning discharges and in fluorescent lights and neon signs. The Physicists’ Other States of Matter Superfluids are fluids that low without resistance. As a result, they will pass through the pores of a container. Scientists have found this phase only in helium, one of the few substances that remain a liquid within a few degrees of absolute zero: -459.67 ˚F or -273.15 ˚C. At absolute zero , atoms and molecules would have the least possible energy. The Physicists’ Other States of Matter Superconductors are solids in which electrons move freely. Once started, am electric current in a superconductor can flow forever without the help of an external power supply. Many metals are superconductors at temperature within few degrees of absolute zero. Others exhibit superconductive properties at temperatures more than 100 degrees or -173.16 ˚C above absolute zero. The Physicists’ Other States of Matter Bose-Einstein Condensates, also known as BEC’s, are clusters of millions of atoms that merge under conditions of extreme cold. BEC’s can form in some gases when they are cooled to within a few billionth of a Celsius degree of absolute zero. When a BEC forms, million of atoms stop moving in different directions at different speeds ad instead act as a single atom. The Physicists’ Other States of Matter The Condensates are named after physicists Satyendranath Bose of India and Albert Einstein of Germany who proposed the possibility of BEC’s in the 1920’s Unusual Forms of Matter Scientists have discovered an unusual form of matter called antimatter. Dark matter which may be fundamentally different from ordinary matter, apparently also exist. Physicists do not know what it is made of, however. Unusual Forms of Matter Antimatter Physicists can convert energy into matter with devices called particle accelerators. When subatomic particles collide at high speeds, they create new particles. Whenever particles of matter are created, an equal number of particles of antimatter are also made. Antimatter particles are equal in mass to the equivalent particles of matter but opposite in electric charge and certain other properties. Unusual Forms of Matter -For example, positrons, which are positively charged, are the antimatter equivalent of electrons. If a matter particle meets an equivalent antimatter particle, the two particles destroy each other. Both particles are converted into energy. Unusual Forms of Matter Antimatter particles are rare and last only until they encounter matter and are destroyed. there appear to be no large concentrations of antimatter anywhere in the universe. On Earth, they are mainly a laboratory curiosity. Medical technology, however, makes use of positrons in a technique called positron emission tomography (PET). PET images reveal the chemical activity of areas of the brain and other body tissues. Unusual Forms of Matter Dark Matter More than 99% of the visible universe is made up of the two lightest kinds of atoms, helium and hydrogen. It appears, however, that most of the matter in the universe is invisible dark matter. Scientists have detected dark matter only through the influence of its gravitational force on the motions of visible matter. Many scientists believe that dark matter is composed of undiscovered particles. Density and Specific Gravity Density- is the mass – that is, the amount of matter – in a unit volume of any substance. Mathematically, D= 𝑀 𝑉 Where: D= Density M= Mass V= Volume Density and Specific Gravity Earth scientists use density measurements to identify minerals and other solids. Chemists measure the density of a solution to determine the concentration of a substance in that solution. They also calculate the molecular weight of a gas from its density. Density in Solids To measure the density of a regular shaped solid, first measure the object’s mass – that is, weigh the object. Next, measure one or more of the object’s dimensions and calculate its volume from a mathematical formula for objects of that shape. Then divide the mass by the volume. Density in Solids It is more difficult to find the density of an irregularly shaped solid because the volume is harder to determine. To determine the volume, submerge the object, then measure the volume of the water displaced. This volume equals the volume of the object. Density in Gases The density of gas is difficult to measure because gases have low densities and the density of gases changes greatly with variations in temperature and pressure. To determine the mass of a gas, first weigh an empty container. Next, fill the container with the gas and weight it again. Density in Gases Then subtract the first measurement from the second. To determine the volume of the container, measure the amount of water that the container holds. Specific Gravity The specific gravity of a substance is related to its density. Specific gravity equals the mass of a given volume of the substance divided by the mass of an equal volume of water. To determine the specific gravity of a substance, divide the density of the substance by the density of water at either 4 ˚C (39 ˚F) or 20 ˚C (68 ˚F).