INORGANIC ANALYSIS Chapter 6 Inorganic Compounds Compounds which
- Slides: 22
INORGANIC ANALYSIS Chapter 6
Inorganic Compounds § Compounds which do not contain carbon § Metals- Tools, coins, weapons, metal scrapings, paints, dyes, explosives, poisons
Trace Elements § Trace elements (<1%) - “invisible” markers, additional points of comparison § Soil, fibers, glass, metallic objects, hair, paint
Atomic Structure § Nucleus- in the center, contains neutrons and § § § protons Protons have a positive charge (1) Electrons have a negative charge (1/1837) Neutrons have a neutral charge (1)
Atomic Structure § Atomic number = the number of protons in the nucleus of an atom, the number identifies the element (also tells the number of electrons) § Atomic mass (mass number) = the number of protons + the number of neutrons
Atomic Structure § Atoms that differ from other atoms of the same element by the number of neutrons in the nucleus (have the same number of protons and electrons) Ex: hydrogen has 3 isotopes – all have 1 proton but each has a different # of neutrons)
Atomic Structure § Electrons travel around the nucleus in orbital paths with § § § particular energy level Excited state- electrons pushed into higher orbitals (requires energy) Atomic Absorption Spectrophotometry- measures the value & amount of light energy going into atom Falls back after short period of time (releases energy) Emission Spectroscopy- collects & measures the various light energies given off E = hf : Energy difference between orbitals equals Planck’s Constant times frequency of light (absorbed or emitted)
Emission Spectroscopy § Emission Spectrum- light (energy) emitted from a § § § source and passed through a prism is separated into its component colors or frequencies Continuous Spectrum- all colors merge to form continuous band (sunlight, incandescent) Line Spectrum- emitted as several individual colored lines representing definite wavelengths or frequencies (sodium lamp, mercury arc, neon) Vaporized, excited matter emits characteristic line spectrum (“fingerprint” of elements)
Emission Spectroscopy
Emission Spectroscopy § Emission spectrograph- instrument which vaporizes, excites, (carbon electrode/ electrical arc) separates frequencies and records the line spectra of elements
ICP § Inductively Coupled Plasma Emission Spectrometry § Identifies and measures elements through light energy emitted by excited atoms using hot plasma torch (argon gas) § Radio- Frequency (RF) coil carries current § Accepted method of identification and characterization of mutilated bullets and glass fragments
Atomic Absorption Spectrophotometer § Light (energy) absorption of element (photon of § § § light interacts w/ an electron jumps to higher orbital) Higher conc. of element more light absorbed Quantitative (even trace elements) Determine one element at a time Graphite furnace or heated strip of metal increases efficiency and sensitivity (one-trillionth of gram) Simple, low cost
Neutron Activation Analysis § § § Nuclear energychanging number of subatomic particles Radioactivity- emission of radiation when unstable nuclei spontaneously disintegrate (radioactive decay) Ex- radium, uranium, thorium
Radioactivity § Three types of radiation: 1)Alpha rays- positively charged helium atoms minus orbiting electrons 2)Beta rays- electrons 3)Gamma rays-high energy form of electromagnetic radiation (*)
Radioactivity
Neutron Activation Analysis § Nondestructive method for identifying and quantitating trace elements § Bombards w/neutrons, measures emitted gamma rays § Extremely sensitive (nanogram) § Simultaneous analysis for 20 -30 elements § Very expensive (nuclear reactor + analyzer) § Metals, drugs, paint, soil, GSR, hair
JFK Assassination § 1963, Lee Harvey Oswald, Warren Commission § 3 shots from Texas School Book Depository behind JFK § JFK hit by 2 bullets 1: back throat Gov. Connally back chest right wrist left thigh 2: JFK’s skull (fatal)
JKF Assassination § Evidence in depository: * 6. 5 -mm military rifle w/Oswald’s palm print * 3 spent 6. 5 mm cartridge cases * Oswald seen in AM and minutes after shooting * “Grassy knoll”?
JFK Assassination § 1977 - Bullet, fragments and wounds examined for trace elements § Western Cartridge Co. /Mannlicher. Carcano bullets contain antimony & silver § Neutron Activation Analysis § Stretcher and wrist bullet indistinguishable § Car and brain fragments indistinguishable § Results consistent with findings § See Table 6 -3 pg. 153
X-Ray Diffraction § Identifies crystalline materials, how elements are combined into compounds § Solid, crystalline materials: definite, orderly arrangement of atoms § 95% of inorganic compounds § Diffraction pattern formed by reflection of X -rays (“fingerprint”) § Not sensitive (<5 % of mixture) § Ex- Explosives
X-ray Diffraction
- Organic and inorganic compounds experiment
- Organic chemistry chapter 1
- Difference between organic and inorganic
- Organic vs inorganic compounds
- Pharmaceutical inorganic chemistry introduction
- Meaning of the word organic
- Ionic, covalent and metallic bonds venn diagram
- Which compound is inorganic
- Inorganic vs organic
- Ionic compounds
- Chapter 7 chapter assessment ionic compounds and metals
- Quantitative analysis of organic compounds ppt
- Which two formulas represent compounds
- Unsaturated solubility
- Which of the following compounds is aromatic?
- Ionic bonds hardness
- Smear layer consists of
- Inorganic plants
- Inorganic chemistry vs organic chemistry
- Is ch4o organic or inorganic
- Organic molecules vs inorganic molecules
- A narrow channel or slab of a mineral
- Organic and inorganic cofactors