eHow - Atomic Structure Information How To's

(image) From 1700 to 1869 scientists had identified more than 60 chemical elements, but there seemed to be no order to the elements, no explanation for their properties. One element would be a neutral gas, but an element that was just barely heavier than the...

(image) Atomic Absorption (AA) spectrophotometry is an instrumental method in chemistry for trace metal analysis. There are two major types of AA spectrophotometers used in laboratories for analysis. The oldest form of AA uses a flame atomization source and...

(image) Each word in the English language offers a unique definition and connotation. Words with similar meanings offer a different tone, sound and appearance. To determine the appropriate word to use in a piece of writing, visualize the word. Visualizing a...

(image) As their name implies, semiconductors are materials that only become good conductors of electricity when certain variables such as the temperature and the amount of energy introduced are adjusted. Semiconductors are critical components in many of the...

(image) Ions are critical components of everything from stars and batteries to living beings. Normal atoms are neutral; that is, they contain a certain number of protons in their nuclei and the exact same number of electrons surrounding the nucleus. If an at...

Strontium is a silvery metallic element with 38 protons in its nucleus. It's found in column 2 of the periodic table, directly beneath calcium and above barium. Scientists have identified no fewer than 16 major radioactive isotopes, although in natur...

(image) Chemical reactions occur at the level of the electron; elements bond to each other or react with one another based on the number of electrons in their "electron shell." Hydrogen has one electron, and its tendency to bond with many other elements rela...

Valence bond (VB) theory is a useful way to explain many properties of molecules. One of the most important concepts in VB theory is orbital hybridization, which is used to explain molecular geometry in organic chemistry. Mathematically, VB theory is...

As electrons are in constant motion around the nucleus of an atom, it is nearly impossible to pinpoint exactly where the electrons located in molecular bonding. However, electrons don't just circle around the nucleus but rather roam in specific areas...

The chemical bonding between molecules and atoms during chemical reactions takes place when the orbitals of different molecules or atoms overlap. The electrons on these overlapped orbitals are shared between the atoms or molecules to fill their incom...

(image) Thoughts, actions and body functions all require signals from the brain --- which is made up of neurons. Neurotransmitters are the chemicals which allow the transmission of signals from one neuron to the next across a gap between neurons called "syna...

(image) Iron is one of the elements on the periodic table. It is a metal no matter what form it takes, and it has a variety of uses. Iron has become an integral part of modern life. It is used to make our consumer goods, treat our waste and keep us healthy.

(image) Though it sounds like science fiction. liquid metallic hydrogen is a fact. Physics theories suggest hydrogen, a gas under ordinary conditions, behaves like a metal under extreme pressures. Scientists have only recently observed it under controlled la...

An indicator, also called a pH indicator, is a halochromic chemical compound that detects hydronium ions (H3O+) or hydrogen ions (H+) in a solution thus indicating whether the solution is acidic or basic. According to ChemiCool, halochromism is the c...

(image) A molecular orbital diagram is a chemical drawing which depicts the region within a molecule where one is most likely to find electrons. Where electrons exist within molecules, how many can be found there and which direction they spin in that locatio...

Electrons are negatively charged particles in an atom. They orbit the positively charged nucleus along a distinct orbital, called an electron shell, within the atom. An electron is a very small particle, measuring 9.1066x10-28 grams. Because the ele...

(image) Soluble silicates, also known as "waterglass" are one of the largest classes of synthetic chemicals, second only to commodity acids and bases in terms of volume. Soluble silicates are highly versatile compounds with many advantageous properties, whic...

Polyurethane is an extremely versatile material that is effective in a wide variety of applications. Polyurethane is unique because of its high elasticity but also its high resistance to damage and spills. Polyurethane can be formed into a number of...

(image) Lewis dot structures simplify the method of indicating how bonding occurs in covalent molecules. Chemists use these diagrams to visualize the association of valence electrons between bonded atoms. To draw a Lewis dot structure for an atom, you must k...

(image) Polyethylene and polyvinyl chloride, or PVC, are plastics that form through a mechanism called radical polymerization. The reaction conditions used for each, however, are different, as are the structures, properties and uses of the finished materials...

(image) Science is a discipline built on constant change. Modern atomic theory is relatively new, with roots barely a century old, yet in that short time, it has undergone radical changes. These changes render older models obsolete or inadequate to fully exp...

(image) Polyethylene and polyurethane are two types of plastic materials used to manufacture a wide range of items, including common consumer goods. There are, however, some distinct differences between these materials in both chemical composition and how th...

Electrons are the negatively charged particles of the atom. Electrons circle the nucleus, which contains the protons and neutrons, at various distances called shells. Each element has a certain number of electrons and shells. Under certain circumstan...

Rutherford's experiment, also known as the gold foil experiment or the Geiger-Marsden experiment, involved firing positively charged alpha particles, which are basically helium nuclei, at a very thin sheet of gold foil surrounded by a detector. The e...

(image) You probably learned early in your science education that opposite charges attract and like charges repel one another. The planetary model of Niels Bohr features the positively charged nucleus surrounded by negatively charged electrons. The opposite...

(image) Atoms are composed of a heavy nucleus surrounded by light electrons. The behavior of the electrons is governed by the rules of quantum mechanics. Those rules allow electrons to occupy specific regions called orbitals. The interactions of atoms are al...

(image) A Bohr diagram is a simplified visual representation of an atom that was developed by Danish physicist Niels Bohr in 1913. The diagram depicts the atom as a positively charged nucleus surrounded by electrons that travel in circular orbits about the n...

(image) The periodic table of the elements is divided into nine groups of elements, based on a number of different characteristics. Among these groups are the transition metals and main group metals. Main group metals are actually a collection of alkali meta...

(image) When two elements react, they form a compound by sharing, donating or accepting electrons. When two significantly different elements bond, such as a metal and a non-metal, one element controls the other's electrons most of the time. While it is not s...

(image) Electrons and orbitals are fundamentally related and form the core of bonding theories in chemistry. According to Purdue University, the location of an electron can never be known exactly, but a region can be calculated where it is probable the elec...

(image) Electronic semiconductors are devices that utilize the special properties of semiconducting elements such as silicon and germanium. The first semiconductor was a diode made from a germanium crystal and was used in radio receivers. After World War II,...

(image) Chemists use the term isomers to refer to chemical compounds that are somehow different from each other even though their molecules have the same types and quantities of atoms. Isomers can result from different types of arrangements of atoms within a...

(image) Chemists depict atoms and molecules using Lewis dot diagrams that show the positioning or placement of electrons. When a bond forms, such as in molecules, instead of using two dots to show the connection you can draw a line between the two atoms invo...

(image) Conductors --- like copper and gold --- allow the free flow of electricity. Insulators --- like carbon and glass --- inhibit the flow of electricity. Semiconductors are materials that fall in the mid range between conductors and insulators. When peop...

(image) Mafic silicates are a general classification of minerals found in igneous rocks. The term "mafic" refers to the minerals' high content of the elements magnesium and iron, combined with oxides of silicon and other elements. Mafic minerals are typicall...

(image) In the periodic table, the so-called inner transition metals are generally shown as an island of 14 elements split off from the remainder of the periodic table. In logical sequence, they follow lanthanum and actinium, respectively --- as a result, th...

(image) Lewis dot diagrams of atoms and ions aid chemists in the determination of which atoms are bound to each other on a simplistic scale. Atoms are most stable when they have enough electrons to fill the valance shell of their electronic structure. Ions a...

(image) Planetariums are places you can go to get a sense of the universe. They help envision an existence beyond limitation and stir the imagination. Planetariums are made up of projected light on domed ceilings in enclosed buildings. The light projected of...

(image) Buckyballs are small metallic balls made of Neodymium, considered one of 17 "rare Earth metals" on the periodic table. Buckyballs are small in diameter (about the size of a pea) and extremely magnetic. They come in a box of 216, 6 inches by 6 inches,...

(image) Many of the concepts you'll encounter in quantum mechanics or quantum chemistry can be difficult to visualize. It's one thing to say, for example, that electrons exhibit both wave-like and particle-like properties, but what does that actually mean? D...

(image) Unlike other solids, crystals have molecules or ions arranged in a well-defined array. All crystals are held together by attractions among molecules. The forces that hold a crystal together, however, vary depending on the kind of crystal and the mole...

(image) All atoms are made of protons, neutrons and electrons. Protons are positively charged; neutrons are neutral in charge; and electrons are negatively charged. Some atoms readily give up electrons, while others readily accept them. You can predict which...

(image) Magnetic materials play a vital role in the technologies produced in today's world. Some of the most important magnetic elements are found within an area of the periodic table known as the "transition metals;" these are iron, cobalt and nickel. These...

(image) The noble gases comprise a group of six elements represented in Group 8A of the Periodic Table of Elements. Noble gases have similar chemical properties: they are generally stable, nonreactive and rarely found in combination with other elements. Heli...

(image) A synapse is a junction between a neuron and another cell (often, though not always, another neuron). Two kinds of synapses are found in nature: chemical and electrical. Chemical synapses function through the release of neurotransmitters by the presy...

(image) Atoms are like two-year-olds: always in motion. Unlike two-year-olds, however, atoms are usually bonded to other atoms. This limits the direction, extent and ways in which the atoms can move. Infrared (IR) spectroscopy uses these atomic movements to...

(image) Isomers are two or more chemical compounds, with the same numbers and types of atoms in their molecules, which are yet not the same. The various kinds of isomers are categorized and named according to the particular way in which they are different. M...

(image) Neon signs are named for the noble gas neon. So, you might assume that all neon signs contain neon, but this is not the case. A variety of noble gases are used to create colorful neon signs because different gases create different colors. The gas is...

(image) In the late 1920s, Linus Pauling and several other chemists tried for the first time to understand chemical bonding in terms of quantum mechanics (at that time a fairly new field of study in physics). The result was valence bond theory. While molecul...

(image) The term "isomer" comes from the Greek words meaning "same parts." Two compounds that are isomers have the same molecular formula -- the same number of carbons, oxygens, hydrogens or other atoms -- but their structures are different. Isomers can be d...