purpose of determining whether they are molecular‚ ionic‚ macromolecular or metallic. Introduction Chemical substances could be named ionic‚ molecular or metallic substance‚ based on the kind of bond present in it. Solid ionic compound is composed of ions‚ which are held together by large electrostatic forces. Bonding in molecular substance is caused by the sharing of electrons by atoms. When the stable aggregates resulting from covalent bonding contain relatively small numbers of atoms‚ they are
Premium Electrical resistance Molecule Chemistry
Review Chemical Bonding Three types of bonds Ionic bond: 2 oppositely charged atoms (Na and Cl) Polar covalent: Unequally shared electrons (H and O) Non polar covalent: Equally shared electrons (C and C) or similar electronegativity Electronegativity and chemical bonding Electronegativity is a measure of the strength in which an atom can attract electrons. A difference of < 0. 5 is non polar covalent bond A difference of 0.5 – 1.7 is polar covalent bond A difference of > 1.7 is ionic bond Intermolecular
Free DNA Protein Enzyme
1. What is the purpose of science? The purpose of science is to understand. With science‚ we ask questions‚ seek answers‚ and prove or disprove our theories and speculations. According to the text on page 10 “Science is a way of knowing about the natural world.” (Citations will be provided at the end of the worksheet‚ rather than a continuous re-pasting each time.) 2. Define organism. Give an example of a unicellular organism. According to the text on page 3‚ “Organisms‚ such as trees and humans
Free Atom Chemical bond Covalent bond
nuc charge‚ decreases across cuz same # o lvls‚ more nuc charge pulls elecs in) * Shielding Effect: extent to which elecs in inner orbits affect bonding of valence elecs * Atomic radius: size o atom (picometrs) (increases down cuz more levels outweigh nuc charge‚ increases to the left cuz of less nuc charge for same number of lvls) * Ionic Radius: radius as an atom becomes an ion (decreases since an element has one fewer energy level as it becomes a positive ion loses electrons) *increases
Free Atom Chemical bond VSEPR theory
Chemical Bonds Ionic: forms by a complete transfer of one or more electrons from one atom to another to form ions (cation and anion). Forms between typical metal and non-metal due to a significant difference in electronegativity (ability of atom to attract electrons; refer to table 1.2). LiF Covalent: forms by sharing electrons between two atoms (polar covalent and non-polar covalent). Forms between non-metals. Electronegativity difference ∆ EN for two elements: ∆ EN > 1.2 Ionic Bond 0.4 < ∆ EN
Premium Chemical bond Molecule Covalent bond
UNIT 1 MATTER‚ CHEMICAL TRENDS AND CHEMICAL BONDING UNIT 1 MATTER AND CHEMICAL BONDING 1.1 The Study of Chemistry Chemistry is the study of matter and its properties‚ the changes (chemical‚ physical‚ and nuclear) that matter experiences‚ and the energy that is associated with these changes. The term STSE refers to science‚ technology‚ society‚ and the environment. These four areas are
Free Atom Periodic table Electron configuration
Introduction Notes What is Science? Study of/tool to understand/body of knowledge/process to understand the natural world What do Scientists do? Make observations Attempt to discern patters Assume the future is like the past What is Biology? The study of life What is Life? Not ever clearly defined Characteristics of living systems: Highly organized Huge energy users 90% of food we eat is used to keep us going Development Development from a single cell to billons of cells Reproduction
Free Atom Chemical bond Electron
mean? 8. Define chemical bond‚ molecule‚ compounds‚ and mixture. (Give examples) 9. Write a chemical equation and indicated the products and reactants. 10. What is an ion? 11. Describe the following bonds (use examples): ionic bond‚ polar covalent bond‚ nonpolar covalent bond‚ and hydrogen bond. 12. What are the properties of water? Describe each property being sure to include the following terms: hydrophobic‚ hydrophilic‚ evaporation‚ cohesion‚ adhesion‚ solvent‚ solute‚ and solution.
Premium Atom Cell Protein
Year 11 Module 1 – The Chemical Earth The Earth is made up of a large number of different substances: elements‚ compounds & mixtures We can classify elements & compounds as pure substances. These are always HOMOGENEOUS. Mixtures are not pure substances and can be either homogeneous or HETEROGENEOUS. Pure substances have a fixed composition eg copper metal‚ sulfur‚ carbon dioxide (CO2)‚ methane (CH4). Mixtures have variable composition and can also be separated into its components relatively
Free Atom Chemical bond Chemistry
“Denaturation of Proteins” Denaturation is a process in which proteins or nucleic acids lose the tertiary structure and secondary structure which is present in their native state‚ by application of some external stress or compound such as a strong acid or base‚ a concentrated inorganic salt‚ an organic solvent (e.g.‚ alcohol or chloroform)‚ or heat. If proteins in a living cell are denatured‚ this results in disruption of cell activity and possibly cell death. Denatured proteins
Premium Protein Amino acid