Than One Atom, Eg, O2, H2, CO, H2O. Compound
Total Page：16
File Type：pdf, Size：1020Kb
Load more
Recommended publications
-
Neutron Stars
Chandra X-Ray Observatory X-Ray Astronomy Field Guide Neutron Stars Ordinary matter, or the stuff we and everything around us is made of, consists largely of empty space. Even a rock is mostly empty space. This is because matter is made of atoms. An atom is a cloud of electrons orbiting around a nucleus composed of protons and neutrons. The nucleus contains more than 99.9 percent of the mass of an atom, yet it has a diameter of only 1/100,000 that of the electron cloud. The electrons themselves take up little space, but the pattern of their orbit defines the size of the atom, which is therefore 99.9999999999999% Chandra Image of Vela Pulsar open space! (NASA/PSU/G.Pavlov et al. What we perceive as painfully solid when we bump against a rock is really a hurly-burly of electrons moving through empty space so fast that we can't see—or feel—the emptiness. What would matter look like if it weren't empty, if we could crush the electron cloud down to the size of the nucleus? Suppose we could generate a force strong enough to crush all the emptiness out of a rock roughly the size of a football stadium. The rock would be squeezed down to the size of a grain of sand and would still weigh 4 million tons! Such extreme forces occur in nature when the central part of a massive star collapses to form a neutron star. The atoms are crushed completely, and the electrons are jammed inside the protons to form a star composed almost entirely of neutrons. -
The Chemical Origin of Behavior Is Rooted in Abiogenesis
Life 2012, 2, 313-322; doi:10.3390/life2040313 OPEN ACCESS life ISSN 2075-1729 www.mdpi.com/journal/life Article The Chemical Origin of Behavior is Rooted in Abiogenesis Brian C. Larson, R. Paul Jensen and Niles Lehman * Department of Chemistry, Portland State University, P.O. Box 751, Portland, OR 97207, USA; E-Mails: [email protected] (B.C.L.); [email protected] (R.P.J.) * Author to whom correspondence should be addressed; E-Mail: [email protected]; Tel.: +1-503-725-8769. Received: 6 August 2012; in revised form: 29 September 2012 / Accepted: 2 November 2012 / Published: 7 November 2012 Abstract: We describe the initial realization of behavior in the biosphere, which we term behavioral chemistry. If molecules are complex enough to attain a stochastic element to their structural conformation in such as a way as to radically affect their function in a biological (evolvable) setting, then they have the capacity to behave. This circumstance is described here as behavioral chemistry, unique in its definition from the colloquial chemical behavior. This transition between chemical behavior and behavioral chemistry need be explicit when discussing the root cause of behavior, which itself lies squarely at the origins of life and is the foundation of choice. RNA polymers of sufficient length meet the criteria for behavioral chemistry and therefore are capable of making a choice. Keywords: behavior; chemistry; free will; RNA; origins of life 1. Introduction Behavior is an integral feature of life. Behavior is manifest when a choice is possible, and a living entity responds to its environment in one of multiple possible ways. -
TEK 8.5C: Periodic Table
Name: Teacher: Pd. Date: TEK 8.5C: Periodic Table TEK 8.5C: Interpret the arrangement of the Periodic Table, including groups and periods, to explain how properties are used to classify elements. Elements and the Periodic Table An element is a substance that cannot be separated into simpler substances by physical or chemical means. An element is already in its simplest form. The smallest piece of an element that still has the properties of that element is called an atom. An element is a pure substance, containing only one kind of atom. The Periodic Table of Elements is a list of all the elements that have been discovered and named, with each element listed in its own element square. Elements are represented on the Periodic Table by a one or two letter symbol, and its name, atomic number and atomic mass. The Periodic Table & Atomic Structure The elements are listed on the Periodic Table in atomic number order, starting at the upper left corner and then moving from the left to right and top to bottom, just as the words of a paragraph are read. The element’s atomic number is based on the number of protons in each atom of that element. In electrically neutral atoms, the atomic number also represents the number of electrons in each atom of that element. For example, the atomic number for neon (Ne) is 10, which means that each atom of neon has 10 protons and 10 electrons. Magnesium (Mg) has an atomic number of 12, which means it has 12 protons and 12 electrons. -
Centripetal Force Is Balanced by the Circular Motion of the Elctron Causing the Centrifugal Force
STANDARD SC1 b. Construct an argument to support the claim that the proton (and not the neutron or electron) defines the element’s identity. c. Construct an explanation based on scientific evidence of the production of elements heavier than hydrogen by nuclear fusion. d. Construct an explanation that relates the relative abundance of isotopes of a particular element to the atomic mass of the element. First, we quickly review pre-requisite concepts One of the most curious observations with atoms is the fact that there are charged particles inside the atom and there is also constant spinning and Warm-up 1: List the name, charge, mass, and location of the three subatomic circling. How does atom remain stable under these conditions? Remember particles Opposite charges attract each other; Like charges repel each other. Your Particle Location Charge Mass in a.m.u. Task: Read the following information and consult with your teacher as STABILITY OF ATOMS needed, answer Warm-Up tasks 2 and 3 on Page 2. (3) Death spiral does not occur at all! This is because the centripetal force is balanced by the circular motion of the elctron causing the centrifugal force. The centrifugal force is the outward force from the center to the circumference of the circle. Electrons not only spin on their own axis, they are also in a constant circular motion around the nucleus. Despite this terrific movement, electrons are very stable. The stability of electrons mainly comes from the electrostatic forces of attraction between the nucleus and the electrons. The electrostatic forces are also known as Coulombic Forces of Attraction. -
Cosmochemistry Cosmic Background Radia On
6/10/13 Cosmochemistry Cosmic background radiaon Dust Anja C. Andersen Niels Bohr Instute University of Copenhagen hp://www.dark-cosmology.dk/~anja Hauser & Dwek 2001 Molecule formation on dust grains Multiwavelenght MW 1 6/10/13 Gas-phase element depleons in the Concept of dust depleon interstellar medium The depleon of an element X in the ISM is defined in terms of (a logarithm of) its reducon factor below the expected abundance relave to that of hydrogen if all of the atoms were in the gas phase, [Xgas/H] = log{N(X)/N(H)} − log(X/H) which is based on the assumpon that solar abundances (X/H)are good reference values that truly reflect the underlying total abundances. In this formula, N(X) is the column density of element X and N(H) represents the column density of hydrogen in both atomic and molecular form, i.e., N(HI) + 2N(H2). The missing atoms of element X are presumed to be locked up in solids within dust grains or large molecules that are difficult to idenfy spectroscopically, with fraconal amounts (again relave to H) given by [Xgas/H] (Xdust/H) = (X/H)(1 − 10 ). Jenkins 2009 Jenkins 2009 2 6/10/13 Jenkins 2009 Jenkins 2009 The Galacc Exncon Curve Extinction curves measure the difference in emitted and observed light. Traditionally measured by comparing two stars of the same spectral type. Galactic Extinction - empirically determined: -1 -1 <A(λ)/A(V)> = a(λ ) + b(λ )/RV (Cardelli et al. 1999) • Bump at 2175 Å (4.6 µm-1) • RV : Ratio of total to selective extinction in the V band • Mean value is RV = 3.1 (blue) • Low value: RV = 1.8 (green) (Udalski 2003) • High value: RV = 5.6-5.8 (red) (Cardelli et al. -
Of the Periodic Table
of the Periodic Table teacher notes Give your students a visual introduction to the families of the periodic table! This product includes eight mini- posters, one for each of the element families on the main group of the periodic table: Alkali Metals, Alkaline Earth Metals, Boron/Aluminum Group (Icosagens), Carbon Group (Crystallogens), Nitrogen Group (Pnictogens), Oxygen Group (Chalcogens), Halogens, and Noble Gases. The mini-posters give overview information about the family as well as a visual of where on the periodic table the family is located and a diagram of an atom of that family highlighting the number of valence electrons. Also included is the student packet, which is broken into the eight families and asks for specific information that students will find on the mini-posters. The students are also directed to color each family with a specific color on the blank graphic organizer at the end of their packet and they go to the fantastic interactive table at www.periodictable.com to learn even more about the elements in each family. Furthermore, there is a section for students to conduct their own research on the element of hydrogen, which does not belong to a family. When I use this activity, I print two of each mini-poster in color (pages 8 through 15 of this file), laminate them, and lay them on a big table. I have students work in partners to read about each family, one at a time, and complete that section of the student packet (pages 16 through 21 of this file). When they finish, they bring the mini-poster back to the table for another group to use. -
Introduction to Chemistry
Introduction to Chemistry Author: Tracy Poulsen Digital Proofer Supported by CK-12 Foundation CK-12 Foundation is a non-profit organization with a mission to reduce the cost of textbook Introduction to Chem... materials for the K-12 market both in the U.S. and worldwide. Using an open-content, web-based Authored by Tracy Poulsen collaborative model termed the “FlexBook,” CK-12 intends to pioneer the generation and 8.5" x 11.0" (21.59 x 27.94 cm) distribution of high-quality educational content that will serve both as core text as well as provide Black & White on White paper an adaptive environment for learning. 250 pages ISBN-13: 9781478298601 Copyright © 2010, CK-12 Foundation, www.ck12.org ISBN-10: 147829860X Except as otherwise noted, all CK-12 Content (including CK-12 Curriculum Material) is made Please carefully review your Digital Proof download for formatting, available to Users in accordance with the Creative Commons Attribution/Non-Commercial/Share grammar, and design issues that may need to be corrected. Alike 3.0 Unported (CC-by-NC-SA) License (http://creativecommons.org/licenses/by-nc- sa/3.0/), as amended and updated by Creative Commons from time to time (the “CC License”), We recommend that you review your book three times, with each time focusing on a different aspect. which is incorporated herein by this reference. Specific details can be found at http://about.ck12.org/terms. Check the format, including headers, footers, page 1 numbers, spacing, table of contents, and index. 2 Review any images or graphics and captions if applicable. -
The Water Molecule
Seawater Chemistry: Key Ideas Water is a polar molecule with the remarkable ability to dissolve more substances than any other natural solvent. Salinity is the measure of dissolved inorganic solids in water. The most abundant ions dissolved in seawater are chloride, sodium, sulfate, and magnesium. The ocean is in steady state (approx. equilibrium). Water density is greatly affected by temperature and salinity Light and sound travel differently in water than they do in air. Oxygen and carbon dioxide are the most important dissolved gases. 1 The Water Molecule Water is a polar molecule with a positive and a negative side. 2 1 Water Molecule Asymmetry of a water molecule and distribution of electrons result in a dipole structure with the oxygen end of the molecule negatively charged and the hydrogen end of the molecule positively charged. 3 The Water Molecule Dipole structure of water molecule produces an electrostatic bond (hydrogen bond) between water molecules. Hydrogen bonds form when the positive end of one water molecule bonds to the negative end of another water molecule. 4 2 Figure 4.1 5 The Dissolving Power of Water As solid sodium chloride dissolves, the positive and negative ions are attracted to the positive and negative ends of the polar water molecules. 6 3 Formation of Hydrated Ions Water dissolves salts by surrounding the atoms in the salt crystal and neutralizing the ionic bond holding the atoms together. 7 Important Property of Water: Heat Capacity Amount of heat to raise T of 1 g by 1oC Water has high heat capacity - 1 calorie Rocks and minerals have low HC ~ 0.2 cal. -
Elements Make up the Periodic Table
Page 1 of 7 KEY CONCEPT Elements make up the periodic table. BEFORE, you learned NOW, you will learn • Atoms have a structure • How the periodic table is • Every element is made from organized a different type of atom • How properties of elements are shown by the periodic table VOCABULARY EXPLORE Similarities and Differences of Objects atomic mass p. 17 How can different objects be organized? periodic table p. 18 group p. 22 PROCEDURE MATERIALS period p. 22 buttons 1 With several classmates, organize the buttons into three or more groups. 2 Compare your team’s organization of the buttons with another team’s organization. WHAT DO YOU THINK? • What characteristics did you use to organize the buttons? • In what other ways could you have organized the buttons? Elements can be organized by similarities. One way of organizing elements is by the masses of their atoms. Finding the masses of atoms was a difficult task for the chemists of the past. They could not place an atom on a pan balance. All they could do was find the mass of a very large number of atoms of a certain element and then infer the mass of a single one of them. Remember that not all the atoms of an element have the same atomic mass number. Elements have isotopes. When chemists attempt to measure the mass of an atom, therefore, they are actually finding the average mass of all its isotopes. The atomic mass of the atoms of an element is the average mass of all the element’s isotopes. -
Make an Atom Vocabulary Grade Levels
MAKE AN ATOM Fundamental to physical science is a basic understanding of the atom. Atoms are comprised of protons, neutrons, and electrons. Protons and neutrons are at the center of the atom while electrons live in lobe-shaped clouds outside the nucleus. The number of electrons usually matches the number of protons, yielding a net neutral charge for the atom. Sometimes an atom has less neutrons or more neutrons than protons. This is called an isotope. If an atom has different numbers of electrons than protons, then it is an ion. If an atom has different numbers of protons, it is a different element all together. Scientists at Idaho National Laboratory study, create, and use radioactive isotopes like Uranium 234. The 234 means this isotope has an atomic mass of 234 Atomic Mass Units (AMU). GRADE LEVELS: 3-8 VOCABULARY Atom – The basic unit of a chemical element. Proton – A stable subatomic particle occurring in all atomic nuclei, with a positive electric charge equal in magnitude to that of an electron, but of opposite sign. Neutron – A subatomic particle of about the same mass as a proton but without an electric charge, present in all atomic nuclei except those of ordinary hydrogen. Electron – A stable subatomic particle with a charge of negative electricity, found in all atoms and acting as the primary carrier of electricity in solids. Orbital – Each of the actual or potential patterns of electron density that may be formed on an atom or molecule by one or more electrons. Ion – An atom or molecule with a net electric charge due to the loss or gain of one or more electrons. -
4.1 History of the Atom Worksheet
Name: _________________________________ Date: __________ Class: _______ 4.1 History of the Atom Worksheet John Dalton (1766 – 1844): John Dalton was an English chemist. His ideas form the atomic theory of matter. Here are his ideas. All elements are composed (made up) of atoms. It is impossible to divide or destroy an atom. All atoms of the same elements are alike. (One atom of oxygen is like another atom of oxygen.) Atoms of different elements are different. (An atom of oxygen is different from an atom of hydrogen.) Atoms of different elements combine to form a compound. These atoms have to be in definite whole number ratios. For example, water is a compound made up of 2 atoms of hydrogen and 1 atom of oxygen (a ratio of 2:1). Three atoms of hydrogen and 2 atoms of oxygen cannot combine to make water. 1. What is the name of John Dalton’s theory? _____________________________________ 2. What are elements made of? ________________________________________________ 3. An atom of hydrogen and an atom of carbon are _________________________________. 4. What are compounds made of? _______________________________________________ 5. The ratio of atoms in HCl is: a) 1:3 b) 2:1 c) 1:1 J. J. Thompson (Late 1800s): J. J. Thompson was an English scientist. He discovered the electron when he was experimenting with gas discharge tubes. He noticed a movement in a tube. He called the movement cathode rays. The rays moved from the negative end of the tube to the positive end. He realized that the rays were made of negatively charged particles – electrons. -
4 Organic Compounds
Name Class Date CHAPTER 3 Chemical Compounds SECTION 4 Organic Compounds National Science BEFORE YOU READ Education Standards After you read this section, you should be able to answer PS 1a, 1b, 1c these questions: • Why are there so many organic compounds? • What are the names and the properties of organic compounds? • What organic compounds are found in living things? How Does Carbon Form Compounds? Most of the chemical compounds that exist contain STUDY TIP carbon. These compounds are called organic compounds. Brainstorm With a partner, Organic compounds are compounds made of molecules write down the names of several of your favorite foods. in which carbon atoms are covalently bonded to other After you have read about atoms. the carbohydrates, lipids, and Every organic compound contains carbon. Carbon proteins, identify which of atoms have four outer electrons. This means that each these groups are in the foods. carbon atom can make four covalent bonds with other atoms. Most organic molecules have two or more carbon atoms linked to one another. READING CHECK The illustrations in the figure below are models of 1. Identify What do most organic molecules. These models are called structural organic molecules have in formulas. They show the order in which atoms in a mol- them? ecule are connected to one another. A line between two element symbols represents a covalent bond, or one pair of shared electrons. Models of Organic Molecules H H H C H H C H H H H C H H H H C H H C H C H H C C H H C C H H C H H C C H H C H H C H C H H H TAKE A LOOK H C H H H H C H H 2.