The Nature of biology and science Cell theory: * All organisms are made of cells and the products of cells * All cells come from pre-existing cells * The cell is the smallest organisational unit Cells have an outer membrane‚ encloses fluid contents of cell (cytoplasm) Robert Hooke (1665): observed dead cells from bark Anton van Leeuwenhoek: described living cells Matthias Schleiden: plant issues Theodor Schwann: animal tissues Bacteria found without nucleus and lacking other membrane-bound
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moving electrons. And what exactly are electrons? They are tiny particles found in atoms. Everything in the universe is made of atoms—every star‚ every tree‚ every animal. The human body is made of atoms. Air and water are‚ too. Atoms are the building blocks of the universe. Atoms are so small that millions of them would fit on the head of a pin. Atoms are made of even smaller particles. The center of an atom is called the nucleus. It is made of particles called protons and neutrons. The protons
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Lecture 7 Intermolecular Force Semester 1: 2014-2015 Instructor Teach Assistants Office Office hours 1 Huynh Kim Lam : Dr. Huỳnh Kim Lâm : Ms. Võ Diệu Ánh Dương Ms. Hồ Như Ngọc : Rm. A1.705 : 9:00-11:00 AM‚ Thursday (LKH) Chemistry for Engineers (CH011IU) - Lecture 7 - Semester 1: 2014-2015 huynhkimlam.iu@gmail.com / lamhuynh.info Molecular forces Intramolecular forces (bonding forces) – exist within each molecule – influence the chemical properties of the substance – are relatively strong
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Chapter 1 Cell Theory- in the 18th century‚ two scientists came up with the cell theory. Schleiden and Schwen. 3 corollaries of the cell theory: -all cells are alike in chemical composition -all cells store and process information in the same way -all cells arise from other cell through cell division 5 types of different Microscopes 1. Light Microscope- produces 2-D image Direct descendants of Hooks scope> take two lenses to a light source> used this to magnify images up to 1‚000 fold.
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Structural Formula * show all atoms and bonds Condensed Structural Formula * Atoms are shown‚ bonds are understood * Atoms bonded to a C atom are listed after it Stick Representation Lines represent bonds * 1 line = single bond * 2 lines = double bond * 3 lines = triple bond C atoms are NOT shown * Assumed at intersection
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seen in all terminated surfaces that both the majority and minority are metallic. When the depth increases the majority states are still metallic and have no distinct change at the Fermi level‚ while the minority states of each atom decrease relative to those of the atoms in the surface. For the Co-Co surface is lost the half–metallic (HM) properties of the bulk system with the spin polarization about –42%. The total density of states (DOS) as well as the projected density of states (PDOS) is shown
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Chapter 4 CLO 1.A branch of chemistry dealing with compounds of Carbon. 2.Carbon’s has 4 valence electrons that can form covalent bonds with others atoms (Hydrogen‚ Nitrogen‚ Oxygen and Carbon atoms mostly) to make large‚ complex and diverse organic molecules. 3.The carbon skeleton vary in 4 areas‚ 1. Length 2. Branching 3. Double Bond Position 4. Presence of Rings. Carbon skeletons can have double bonds in different locations and also different numbers of double bonds. 4.Hydrocarbons
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electrons do atoms of each element have? a. nitrogen d. barium b. lithium e. bromine c. phosphorus f. carbon 37. Name each ion in Problem 36. Identify each as an anion or a cation. 7.2 Ionic Bonds and Ionic Compounds 38. Define an ionic bond. 39. Explain why ionic compounds are electrically 29. Write electron dot structures for each of the fol- lowing elements: a. Cl b. S c. Al d. Li neutral. *40. 30. Describe two ways that an ion forms from an atom. *
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Jeff Fry – Chemistry 11 Section Assignment 3.1: Determining Atomic Mass Instructions Perform the following calculations. Take care to give answers with the appropriate units and significant figures. Show your solution method clearly. The use of a Periodic Table will be required. 1. Element "E" (not a real symbol for an element)‚ has three naturally occurring isotopes: 60% 228E‚ 25.0% 222E‚ and 15.0% 232E. Use this information to determine the atomic mass of element "E". Atomic Mass =
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03.04 Valence Electrons and Bonding Individual neutral atoms are rarely found in nature. The noble gases are the only elements that are found as single atoms more often than they are found in compounds. Atoms are held together in compounds by electrostatic attraction between positive nuclei and negative electrons. This attraction holds atoms together in a chemical bond‚ a link between two atoms resulting from the mutual attraction of their nuclei for valence electrons. All chemical bonds involve
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