Slide 1 Scientific Method Do experiments and collect data Formulate hypothesis to explain data Do more experiments to test hypothesis Revise hypothesis if necessary © 2004 Brooks/Cole – Thomson Learning OBSERVE Ask a question Experimental Design Control Groups Experimental Groups Compare and Analyze

Slide 2 Interpret data Well-tested and accepted hypotheses become scientific theories EXTREMELY well-tested and accepted patterns In data become scientific laws

Slide 3 Chemistry Atoms Isotopes Electron configuration –Valence electons –periodic Molecules –Diatomic –More Bonding types

Slide 4 Click to view animation. Subatomic particles interaction. Animation

Slide 5 Animation Click to view animation. Atomic number, mass number interaction.

Slide 6 Hydrogen (H) 0 n1 p0 n1 p 1e1e 1 n1 p1 n1 p 2 n1 p2 n1 p 1e1e1e1e Mass number = = 1 Hydrogen-1 (99.98%) Mass number = = 2 Hydrogen-2 or deuterium (0.015%) Mass number = = 3 Hydrogen-3 or tritium (T) (trace) Uranium (U) 143 n 92 p 146 n 92 p 92e Mass number = = 235 Uranium-235 (0.7%) Mass number = = 238 Uranium-238 (99.3%) Figure 3-5 Page 52 © 2004 Brooks/Cole – Thomson Learning

Slide 7 Click to view animation. Positron emission tomography (PET) animation. Animation

Slide 8 Click to view animation. Ionic bonding animation. Animation

Slide 9 Reactant(s) carbon + oxygen C + O 2 CO 2 + energy carbon dioxide + energy + energy Product(s) black solidcolorless gas C O O OOC In-text figure Page 56

Slide 10 High Quality Solid Salt Coal Gasoline Aluminum can Low Quality Gas Solution of salt in water Coal-fired power plant emissions Automobile emissions Aluminum ore Figure 3-6 Page 53 © 2004 Brooks/Cole – Thomson Learning

Slide 11 What are isotopes? p p n p n n Protium DeuteriumTritium These atoms are isotopes of hydrogen. They all have one proton and one electron, but different numbers of neutrons.

Slide 12 What is radioactivity? p n n p n p An unstable nucleus, like tritium will eject an energetic particle and transform into an atom of helium-3 ( 3 He ) 3H3H 3 He

Slide 13 While tritium is radioactive, the energy of the beta particle is very low. Tritium is the only radioactive isotope that you can buy in large quantities at the local mall. The tritium present in the entire Livermore Valley groundwater basin equals that found in 30 ‘tritium dial’ watches

Slide 14 What is a half-life ? The half-life is a measure of the rate of decay In one half-life, half of the atoms decay 1000 Tritium Atoms Time (years)

Slide 15 For every tritium decay, an atom of 3 He is produced

Slide 16 The 3 He from 3 H decay starts to accumulate once the water has become groundwater Age (years) = 18 x ln( He / 3 H ) 0 years12 years24 years

Slide 17 Fission fragment Energy n n n n Uranium-235 nucleus Unstable nucleus Figure 3-11 Page 58

Slide 18 n U Kr Ba n n n Kr U U Ba Kr Ba Kr Ba n n n n n n n n U U U U n Figure 3-12 Page 58

Slide 19 FuelReaction ConditionsProducts D-T Fusion Hydrogen-2 or deuterium nucleus Hydrogen-3 or tritium nucleus Hydrogen-2 or deuterium nucleus Hydrogen-2 or deuterium nucleus D-D Fusion Neutron Energy ++ Helium-4 nucleus ++ Helium-3 nucleus Energy Neutron million ˚C 1 billion ˚C Neutron Proton + Figure 3-13 Page 59 © 2004 Brooks/Cole – Thomson Learning

Slide 20 Animation Click to view animation. Half-life interaction.

Slide 21 Energy

Slide 22 Types of Energy Potential –Stored chemical –Physical position Kinetic –Motion –Temperature / Heat

Slide 23 Metabolic Use of Energy Homeostasis Feedback Loops Heat Production

Slide 24 Rate of metabolic chemical reactions Heat input from sun and metabolism Heat loss from air cooling skin Heat in body Positive feedback loop Blood temperature in hypothalamus Excess temperature perceived by brain Sweat production by skin Negative feedback loop Figure 3-3 Page 50

Slide 25 Click to view animation. Homeostatic control of temperature animation. Animation

Slide 26 Animation Click to view animation. Total energy remains constant animation.

Slide 27 1 st Law of Thermodynamics

Slide 28 Animation Click to view animation. Example of mechanical work animation.

Slide 29 Sun High energy, short wavelength Low energy, long wavelength Ionizing radiation Nonionizing radiation Cosmic rays Gamma rays X rays Far ultraviolet waves Near ultraviolet waves Visible waves Near infrared waves Far infrared waves Microwaves TV waves Radio waves Wavelength in meters (not to scale) Figure 3-7 Page 54

Slide 30 Figure 3-8 Page 54 Energy emitted from sun (Kcal/cm 2 /min) Wavelength (micrometers)

Slide 31 Figure 3-9 Page 55 ConvectionConductionRadiation Heat from a stove burner causes atoms or molecules in the pan’s bottom to vibrate faster. The vibrating atoms or molecules then collide with nearby atoms or molecules, causing them to vibrate faster. Eventually, molecules or atoms in the pan’s handle are vibrating so fast it becomes too hot to touch. As the water boils, heat from the hot stove burner and pan radiate into the surrounding air, even though air conducts very little heat. Heating water in the bottom of a pan causes some of the water to vaporize into bubbles. Because they are lighter than the surrounding water, they rise. Water then sinks from the top to replace the rising bubbles.This up and down movement (convection) eventually heats all of the water.

Slide 32 Figure 3-10 Page 55 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) Very high High Moderate Low Source of Energy Relative Energy Quality (usefulness) Energy Tasks Very–high-temperature heat (greater than 2,500°C) for industrial processes and producing electricity to run electrical devices (lights, motors) Mechanical motion (to move vehicles and other things) High-temperature heat (1,000–2,500°C) for industrial processes and producing electricity Moderate-temperature heat (100–1,000°C) for industrial processes, cooking, producing steam, electricity, and hot water Low-temperature heat (100°C or less) for space heating © 2004 Brooks/Cole – Thomson Learning

Slide 33 Solar energy Waste heat Chemical energy (photosynthesis) Waste heat Waste heat Waste heat Chemical energy (food) Mechanical energy (moving, thinking, living) Figure 3-14 Page 60

Slide 34 2nd Law of Thermodynamics

Slide 35 Click to view animation. Animation Energy flow animation.

Slide 36 System Throughputs Inputs (from environment) Outputs (into environment High-quality energy Matter Low-quality energy (heat) Waste and pollution Unsustainable high-waste economy Figure 3-15 Page 61

Slide 37 Inputs (from environment) System Throughputs Outputs (into environment) Energy Matter Energy conservation Waste and pollution prevention Sustainable low-waste economy Recycle and reuse Pollution control Waste and pollution Low-quality energy (heat) Figure 3-16 Page 61