* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download APES Ch. 3 Notes
X-ray photoelectron spectroscopy wikipedia , lookup
Chemical thermodynamics wikipedia , lookup
X-ray fluorescence wikipedia , lookup
Nuclear binding energy wikipedia , lookup
Internal energy wikipedia , lookup
Atomic nucleus wikipedia , lookup
Rutherford backscattering spectrometry wikipedia , lookup
APES Ch. 3 Notes Science, Systems, Matter, and Energy IX. Matter: Forms, Structure and Quality Matter – anything that has mass and takes up space. Calcite mixture Gold (Au) (CaCO3) a. Elements – distinctive building blocks of matter that make up every material substance. b. Compounds – two or more elements held together by chemical bonds. c. Mixture – a combination of two or more elements and compounds. Building Blocks of Elements and Compounds a. Atoms – smallest unit of matter that is unique to a particular element b. Ions – electrically charged atoms or combinations of atoms c. Molecules – combinations of two or more atoms of the same or different element held together by chemical bonds. Forms of Matter a. solid – most compact and orderly arrangement b. liquid c. gas – least compact and orderly arrangement Energy absorbed solid Melting Evaporation And boiling Freezing Condensation liquid Energy released gas Fig. 3.5, p. 54 Components of Atoms a. Proton – positively charged subatomic particle with a mass of 1 (in nucleus) b. Neutron- neutrally charged subatomic particle with a mass of 1 (in nucleus c. Electron – negatively charged subatomic particle with a mass of 0 (outside nucleus) Atomic Number – total number of protons in an atom Atomic Mass – total number of protons and neutrons in an atom Mass # 4 Atomic # 2 He Hydrogen (H) 0n 1p 1n 1p 1e Mass number = 0 + 1 = 1 Hydrogen-1 (99.98%) 2n 1p 1e Mass number = 1 + 1 = 2 Hydrogen-2 or deuterium (0.015%) 1e Mass number = 2 + 1 = 3 Hydrogen-3 or tritium (T) (trace) Uranium (U) 143 n 92 p Mass number = 143 + 92 = 235 Uranium-235 (0.7%) 92e 146 143 n 92 p 92e Mass number = 146 + 92 = 238 Uranium-238 (99.3%) Atomic Number – total number of protons it an atom Atomic Mass – total number of protons and neutrons in an atom Fig. 3.6, p. 55 PH – (pH) – measure of the concentration of hydrogen ions [H+] in a water solution. Concentration=.001 = 10-3 = pH = 3 Fig. 3.7, p. 56 Chemical Formula – shows the number of atoms of each type in a compound. C3H8 = methane Organic Compounds – contain both carbon (C) and hydrogen (H) a. Hydrocarbons b. Chlorinated Hydrocarbons c. Chlorofluorocarbons d. Carbohydrates e. Lipids f. Proteins g. Nucleic Acids Inorganic Compounds – do not contain both carbon (C) and hydrogen (H), but may contain one or the other. a. NaCl g. NO2 b. H2O h. SO2 c. N2O i. NH3 d. NO j. H2S e. CO k. H2SO4 f. CO2 l. HNO3 • • • • Matter Quality – measure of how useful a form of matter is to us as a resource, based on its availability of concentration. a. High Quality Matter – organized, concentrated, found near earth’s surface, and has great potential for use as a matter resource. b. Low Quality Matter – disorganized, dilute, deep underground or dispersed in oceans or the atmosphere, and has little potential for use as a matter resource. Entropy – measure of the disorder or randomness of a system or its environment Material Efficiency (resource productivity) – total amount of material needed to produce each unit of goods or services. High Quality Low Quality Solid Gas Salt Solution of salt in water Coal Coal-fired power plant emissions Gasoline Automobile emissions Fig. 3.9, p. 57 Aluminum can Aluminum ore Energy: Forms and Quality: • Energy – the capacity to do work (move something) and transfer heat. • Kinetic Energy – the energy that matter has due to its mass and speed or velocity. a. b. c. d. e. f. g. Wind Flowing Streams Heat (flowing from high to low) Electricity Electromagnetic Radiation Heat (total kinetic energy of all the moving atoms, ions, or molecules within a given substance) Temperature (the average speed of motion of atoms, ions, or molecules in a sample of matter at a given moment) Potential Energy – the stored energy that is potentially available for use (can be changed into kinetic energy). a. gasoline b. rock at the top of a hill c. nuclear energy XIII. Energy Two Laws of • Law of Conservation of Energy (First Law of Energy or First Law of Thermodynamics) - in all physical and chemical changes, energy is neither created or destroyed, but it may be converted from one form to another. • -energy input always equals energy output • -cannot get something for nothing in terms of energy quantity • Law of Conservation of Energy – We may change various forms of energy from one form to another, but in no physical or chemical change can we create or destroy any of the energy involved. (there is no away) Energy can b changed from one form to another Second Law of Energy or Thermodynamics • – when energy is changed from one form to another, some of the useful energy is always degraded to lower quality, more dispersed, less useful energy. - heat always flows spontaneously from hot (high quality energy) to cold (low quality energy). • - we can not even break even in terms of energy, energy always goes from a more useful to less useful form. • You cant break even (photosynthesis) Waste heat Mechanical energy Chemical energy (food) Chemical energy Solar energy Waste heat (moving, thinking, living) Waste heat Waste heat Fig. 3.18, p. 66 Energy efficiency • Energy efficiency is the ratio of work that is done to the total amount of energy that was introduced into the system in the first place. Energy Input – potential energy from gasoline Energy Output -useful energy, kinetic which moves the car -waste energy, heat from friction, tires, brakes, sound Energy efficiency is expressed in a percent, for example 70% efficient means 70% of energy is used to do work and 30% is lost as heat • • • • • For example Coal to electricty is 35% Transport of electricity is 90% Light bulb is 5% Then when you burn coal the amoiunt of that energy used to actually make light is • .35x.90x.05=.016 or 1.6% • 1.6% of the coal burned was used to make light, 98.4% is lost as heat Sun High energy, short wavelength Low energy, long wavelength Nonionizing radiation Ionizing radiation Cosmic rays Gamma rays 10-14 X rays 10-12 Visible Far Near ultraviolet ultraviolet waves waves waves 10-8 10-7 10-6 Near infrared waves 10-5 Far infrared waves microwaves 10-3 TV waves 10-2 10-1 Radio waves 1 Wavelength in meters (not to scale) Fig. 3.10, p. 58 Energy Quality – measure of an energy source’s ability to do useful work. a. High energy quality – organized or concentrated and can perform much useful work. b. Low energy quality – disorganized or dispersed and has little ability to do useful work. Electricity Very high temperature heat (greater than 2,500°C) Nuclear fission (uranium) Nuclear fusion (deuterium) Concentrated sunlight High-velocity wind High-temperature heat (1,000–2,500°C) Hydrogen gas Natural gas Gasoline Coal Food Normal sunlight Moderate-velocity wind High-velocity water flow Concentrated geothermal energy Moderate-temperature heat (100–1,000°C) Wood and crop wastes Dispersed geothermal energy Low-temperature heat (100°C or lower) Source of Energy Very high Very high-temperature heat (greater than 2,500°C) for industrial processes and producing electricity to run electrical devices (lights, motors) High Mechanical motion (to move vehicles and other things) High-temperature heat (1,000–2,500°C) for industrial processes and producing electricity Moderate Moderate-temperature heat (100–1,000°C) for industrial processes, cooking, producing steam, electricity, and hot water Low Relative Energy Quality (usefulness) Low-temperature heat (100°C or less) for space heating Energy tasks Fig. 3.11, p. 59 • Law of Conservation of Matter – We may change various elements and compounds from one physical or chemical for to another, but in no physical or chemical change can we create or destroy any of the atoms involved. (there is no away) XII. Nuclear Changes – occur when nuclei or certain isotopes spontaneously change into one or more different isotopes. • Natural Radioactive Decay – a nuclear change in which unstable isotopes (radioactive isotopes or radioisotopes) spontaneously emit fast moving chunks of matter called particles, high energy radiation, or both at a fixed rate. a. Gamma Rays – a form of high energy electromagnetic radiation (ionizing energy) b. Alpha Particles – fast moving positively charged chunks of matter consisting of 2 protons and two neutrons 9 (ionizing particle), harmful when inhaled or ingested, can cause skin cancer. c. Beta Particles – High speed electrons (ionizing particle), can damage internal organs even when not ingested or inhaled. Waves 2 protons & 2 neutrons Negative particle like an electron Sheet of paper Block of wood Concrete wall Alpha Beta Gamma Fig. 3.12, p. 62 Radioactive decay series of Uranium • Half Life – the time needed for one half of the nuclei in a radioisotope to decay and emit their radiation to form a different isotope (results in a series of different radioisotopes until a non-radioactive isotope is formed) Fraction of original amount of plutonium-239 left 1 1/2 1/4 1/8 1st half-life 2nd half-life 3rd half-life 0 240,000 480,000 Time (years) 720,000 Fig. 3.13, p. 62 Other 1% Consumer products 3% Radon 55% Nuclear medicine 4% Medical X rays 10% Natural sources 82% Human-generated 18% Space 8% The human body 11% Earth 8% Fig. 3.14, p. 63 Effects of Ionizing Radiation • Causes: • 1. Penetrating a Cell • 2. Altering a cellular chemical by knocking an electron loose. • 3. altering molecules needed for normal chemical functioning • Types: • 1. Genetic Damage – mutations to DNA molecules that alter genes and chromosomes. (possibly passed to following generations) • 2. Somatic Damage – to tissues, which cause harm during a lifetime (burns, cancers) Effects of Ionizing radiation Effects of Nonionizing Radiation (Electromagnetic Radiation) • – Not Known • Sources: • 1. Power Lines • 2. Electrical Appliances • Possible Effects: • 1. Cancer (childhood leukemia, brain tumors, breast cancer) • 2. Miscarriages • 3. Birth Defects • 4. Alzheimer’s Disease Effects of Cell Phones Useful Applications of Radioisotopes 1. Radiocarbon Dating – estimates age of carbon containing substances from dead plants and animals. 2. Tracers – in pollution detection (pipelines) 3. Nuclear Medicine – diagnosis and treatment of disease (cancer) Fission fragment n n n Energy n Uranium-235 nucleus Unstable nucleus Fission fragment Fig. 3.15, p. 64 235 92 U n 92 36 Kr n 235 92 U 92 36 Kr 235 92 U n n 141 Ba 56 n 92 Kr 36 n n n n 235 92 U n 141 56 Ba 141 Ba 56 92 Kr n 36 235 92 U n 141 Ba 56 235 92 U n 235 92 U Fig. 3.16, p. 64 Fuel Reaction Conditions Products D-T Fusion Neutron + Hydrogen-2 or deuterium nucleus + + + 100 million ˚C Energy + + Helium-4 nucleus Hydrogen-3 or tritium nucleus D-D Fusion + + + Helium-3 nucleus Hydrogen-2 or deuterium nucleus + + Energy + + Proton Neutron Hydrogen-2 or deuterium nucleus 1 billion ˚C Neutron Fig. 3.17, p. 64