CHEM 2500 Tulane Exam 1 Questions And Answers

"avaliable" energy resources - the availability of these resources depends on the cost and energy needed to extract and process these resources. Advantages of Coal - 1. Abundant 2. Cheep to transport Advantages of Natural Gas - Clean fuel, requires very little processing, readily transported over land through pipelines. It's carbon dioxide emission rate, per unit of energy, is lower than all other fossil fuels. It contributes less to smog formation than gasoline does. Advantages of Petroleum - It is a liquid = easily transported relatively clean; because sulfur and metallic containing compounds stay in the residue they are not released into the atmosphere very efficient extraction, transport, refining, and delivery technologies albedo - About 30% of the overall quantity of energy that comes from the sun to the Earth (54.4 x 10^20 kJ/year). Contributes significantly to the overall energy balance of the Earth. Alkylation - Some reactors transform molecules chemically in order to match the needs of the markets. The fraction of carbon atoms for gasoline is at high demand. This process enhances the gassoline fraction by building up mid-sized molecules from two smaller ones. This process is catalyzed by strong acids. Alpha Ray/Emission - A nucleus can be unstable by simply having too many protons. When this occurs, the nucleus ejects a particle containing two protons and two neutrons, meaning a helium nucleus (a mass of 4 and an atomic number of 2). [this will effect a radioactive isotope by creating a new element that is 4 mass units lower and 2 atomic numbers lower]. Alternating Currents - electrons go back and forth, examples include what is brought into your home and what comes out of your outlets.Beta Ray/Emission - If there are too many neutrons, one of them may convert into a proton by ejecting an electron. This electron is carried off at a very high speed. A new element is formed during this process because the nucleus becomes more positive (neutron becomes a proton). [this can also be a positron, which is an anti-electron] [this will effect a radioactive isotope by raising the atomic number by one, forming a new element, but it will not effect the mass (because an electron's mass is essentially zero)]. Biological Effects of Alpha Rays - produces intense damage over a short distance, it produces about 200,000 ionizations in the first 400,000 atoms it encounters. BUT the good thing here is that the alpha ray will only penetrate biological tissue up to 0.05mm. Without it having access to the inside of our bodies, it can not do much damage. When alpha emitting particles are ingested, then a serious health issue is at hand. (Ex. Uranium miners and the effects of radon).