Elements 89 to 103 (between lawrencium and actinium) on the periodic table. Only the first four have been found in nature in appreciable amounts. The remainder have been produced synthetically.
All actinides are radioactive, highly electropositive, tarnish readily in air, react with boiling water or dilute acid to release hydrogen gas and combine directly with most nonmetals.
- What are Compound Microscopes?
Most of the microscopes used today are compound. A compound microscope features two or more lenses. A hollow cylinder called the tube connects the two lenses. The top lens, the one people look through, is called the eyepiece. The bottom lens is known as the objective lens. Below the two lenses is...
- Chemical Safety
People use chemicals every day for a wide array of purposes, which can include work and house hold duties. Many of us fail to realize that we are actually handling potentially deadly chemicals when we simply clean the bathroom or wash the car. This brings to mind the reason why chemical safety is...
- Harmful Chemicals Found In Food
It's getting close to New Years and many people are starting to think about how to lose those extra pounds they managed to gain over the holidays. There are many sorts of diets and fads that have developed over the years from cutting carbs to cutting protein. Everyone has their own opinion as to...
- Protein Design: Automated protein discovery and synthesis
In this paper I describe (theoretically) the method(s) of automated protein discovery and synthesis.
- Features of the Scanning Tunneling Microscope
The scanning tunneling microscope (STM) invented by Heinrich Rohrer and Gerd Binnig in the 1980s still manages to do a great job today and competes with more advanced microscope types. The scanning tunneling microscope is used for studying the surface atoms that are found on various materials. The...
A measure of the amount of matter in an object. Mass is usually measured in grams or kilograms.
The direct solidification of a vapor by cooling, the reverse of sublimation.
Trapping of heat at the surface of the earth by carbon dioxide and water vapour in the atmosphere.
Oxidation of metals in the presence of air and moisture.
Discovered : at both Berkeley, California, USA, and Dubna, near Moscow, Russia in 1970. Description:A highly radioactive metal which does not occur naturally, and of which only a few atoms have ever been made. It is of research interest only. Origin:The element is named after the Russian town of Dubna.
A compound formed by interaction of sucrose with a metallic oxide, usually lime, and useful in the purification of sugar.
Valence Shell Electron Pair Repulsion Theory
Assumes that electron pairs are arranged around the central element of a molecule or polyatomic ion so that there is maximum separation (and minimum repulsion) among regions of high electron density.
The ability of one liquid to mix with (dissolve in) another liquid.
The separation of a liquid mixture into its components on the basis of differences in boiling points. The process in which components of a mixture are separated by boiling away the more volitile liquid.
Short-lived species formed by the collision of dissolved ions of opposite charges.
The percent of a specified compound or element in an impure sample.
Mixing a set of atomic orbitals to form a new set of atomic orbitals with the same total electron capacity and with properties and energies intermediate between those of the original unhybridized orbitals.
Collision between molecules resulting in a reaction, one in which the molecules collide with proper relative orientations and sufficient energy to react.
A colorless, crystalline compound, XeF4, prepared by heating a gaseous mixture of fluorine and xenon.
Adhesion of a species onto the surfaces of particles.
Solubility Product Principle
The solubility product constant expression for a slightly soluble compound is the product of the concentrations of the constituent ions, each raised to the power that corresponds to the number of ions in one formula unit.
Compounds that contain the same number of the same kinds of atoms in different geometric arrangements.
Conduction of electrical current by ions through a solution or pure liquid.
Rods of materials such as cadmium or boron steel that act as neutron obsorbers (not merely moderaters) used in nuclear reactors to control neutron fluxes and therfore rates of fission.
Solid triester of glycerol and (mostly) saturated fatty acids.