Matter and Energy

1. Matter and Energy Breaking it down and reviewing old material.

2. What are Nature’s “building blocks”? • Matter – anything that occupies space and has mass. • Matter can be found in the form of elements (distinctive building blocks) and compounds (two or more elements bonded together). • Various elements, compounds, or both can be found in mixtures. • Saltwater? • Silver bar? • Table salt?

3. Phases of Matter • Matter is found, essentially, in three states: • Solid – atoms arranged in close proximity. • Liquid – atoms arranged in a more dispersed pattern. • Gas – atoms widely spaced.

4. Atoms, Ions, and Isotopes • Atoms – the smallest component of an element displaying all characteristics of that element. • Sub-atomic particles – • Protons – found in nucleus, + charge, 1 AMU • Neutrons – found in nucleus, no charge, 1 AMU • Electrons – found orbiting nucleus, - charge, approximately 1/1836 AMU

5. Ions and Isotopes • Ions – charged atoms due to having gained or lost electrons. • Why do ions form? • Examples of ions? • Isotopes – atoms with the same atomic number but different atomic mass. • Why the difference in mass? • Examples of isotopes?

6. Bonds • Ionic compounds are compounds made up of oppositely charged ions. • The classic example would be table salt (NaCl). • Covalent compounds are formed from uncharged atoms. • The classic example would be water (H2O).

7. Simple Organic Compounds • Based on carbon atoms bonded with one or more other elements, such as: hydrogen, oxygen, nitrogen, sulfur, phosphorus, chlorine, and fluorine. • Types of organic molecules include: • Hydrocarbons – CH4, C8H18 • Chlorinated hydrocarbons – DDT, PCBs • Chlorofluorocarbons – CFCs • Simple carbohydrates – C6H12O6

8. Complex Organic Molecules • Composed of polymers of simple organic molecules. • Examples include: • Complex carbohydrates – formed from simple carbohydrates • Proteins – formed from amino acids • Lipids – formed from excess carbohydrates • Nucleic acids – formed from nucleotides • Genes – composed of specific sequences of nucleotides in a DNA molecule • Chromosomes – combinations of genes

9. Inorganic Compounds • Basically, everything else. • Stuff like H2, CO2, O2, O3, NaCl, NaOH, N2, N2O, NO, NH3, H2SO4

10. Matter Quality • A measure of how useful a matter resource is, based on availability and concentration. • High-Quality Matter is organized, concentrated, usually found near the surface of the Earth, and has great potential as a matter resource. • Low-Quality Matter is disorganized, dilute, usually found deep in the Earth or oceans, and has little potential use as a resource.

11. Energy • The ability to do work (and transfer heat). • Forms of energy – • Light • Heat • Electricity • Chemical • Mechanical • Nuclear

12. Energy Classification • Potential – stored and contingent on position. • Height • Chemical • Nuclear forces • Kinetic – contingent on mass and velocity. • Heat • Temperature • Electromagnetic Energy

13. Energy Quality • Like Matter Quality, Energy Quality is dependent on how useful it is to us. • High-Quality Energy – • Gasoline • Sunlight • Uranium nuclei • Low-Quality Energy – • Heat in the atmosphere or oceans • Waste heat

14. It’s not just a good idea, it’s the Law(s)! • Conservation of Matter – there is no “away”. • While we utilize resources and seem to “consume” matter, we are really doing nothing more than rearranging the atoms involved.

15. The Laws of Thermodynamics • 1st Law – In all physical and chemical changes, energy is neither created nor destroyed, but it may be converted from one form to another. • 2nd Law – When energy is converted from one form to another, some of the useful energy is always degraded to lower-quality, more dispersed (higher entropy), less-useful energy. Entropy is a measure of disorder. Therefore, it is always increasing. “Entropy always wins.” • 3rd Law – The entropy of a perfect crystal at absolute zero is exactly equal to zero. • Zeroth Law – if two systems are both in thermal equilibrium with a third, then they are in thermal equilibrium with each other.

16. Matter Changes • Physical – involves no change in chemical composition. Examples include splitting wood, mixing cake batter ingredients, and shaping metal. • Chemical – involves a change to the chemical composition of a substance. Examples include burning wood, baking cake batter, and metal rusting. • Nuclear – certain isotopes are so unstable they are able to spontaneously rearrange themselves and form new isotopes. These processes are known as radioactive decay, fission, and fusion.

17. Nuclear Changes • Radioactive decay occurs when unstable isotopes rearrange their nuclei and release bursts of energy in the form of high-energy particles that are ionizing. • As they rearrange themselves, they become a different, more stable isotope at a predictable rate. • The amount of time it takes for 50% of a substance to naturally degrade to a stable isotope is expressed as its “half-life”. • Radioactive substances are deemed to be safe after 10 half-life cycles.

18. Typical half-life periods • Potassium-42 – 12.4 hours • Iodine-131 – 8 days • Cobalt-60 – 5.27 years • Tritium – 12.5 years • Strontium-90 – 28 years • Carbon-14 – 5,370 years • Plutonium-239 – 24,000 years • Uranium-235 – 710 million years • Uranium-238 – 4.5 billion years

19. Nuclear Fission • Large, unstable isotope nuclei are struck by neutrons and split into smaller nuclei. • When these nuclei split, energy and additional neutrons are release. • A chain reaction will occur as long as sufficient additional nuclei are present.

20. Nuclear Fusion • Two light elements, usually hydrogen isotopes, are combined to form a larger atom. • D-T = 100 million Co • D-D = 1 billion Co

21. Finally, Societies • High-throughput (high-waste) societies attempt to avoid the impact of the 2nd Law of thermodynamics by utilizing increasing amounts of energy and matter to sustain themselves. Ultimately, they are unsustainable. • Matter-recycling societies attempt to mitigate their impact through recycling efforts. The amount of energy becomes the limiting factor. • Low-waste societies are sometimes referred to as Earth-wisdom societies and attempt to live in equilibrium with matter and energy resources available.