User Rating: 0 / 5

Star InactiveStar InactiveStar InactiveStar InactiveStar Inactive
 

Absorption of high energy radiation by a substance and subsequent emission of visible light.

Latest Articles

  • 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...

  • Protein Design: Automated protein discovery and synthesis

    In this paper I describe (theoretically) the method(s) of automated protein discovery and synthesis.

  • What's In Your Beverage? How to Ensure Quality Control with CO2 Analytical Support

    Calibration standards, performance audits, and the FDA's never-ending safety, labeling, and inspection requirements are just the tip of the iceberg when it comes to dealing with the increasingly stringent quality control standards of the beverage industry. As these quality standards become...

  • 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...

  • Diamonds Are Forever

    Diamonds are still a girl's best friend, right? We love the shiny gems. They are the most popular rocks sold today. But what exactly are they, anyway? Where do they come from? What else are they used for?



Most Popular

Free Radical

A highly reactive chemical species carrying no charge and having a single unpaired electron in an orbital.

Ideal Gas

A hypothetical gas that obeys exactly all postulates of the kinetic-molecular theory.

 

Continuous Spectrum

Spectrum that contains all wave-lengths in a specified region of the electromagnetic spectrum.

Cis-

The prefix used to indicate that groups are located on the same side of a bon about which rotation is restricted.

Electron Affinity

The amount of energy absorbed in the process in which an electron is added to a neutral isolated gaseous atom to form a gaseous ion with a 1- charge, has a negative value if energy is released.

Freezing Point Depression

The decrease in the freezing point of a solvent caused by the presence of a solute.ing Point

Lead Storage Battery

Secondary voltaic cell used in most automobiles.

Graham's Law

The rates of effusion of gases are inversely proportional to the square roots of their molecular weights or densities.

Hydrolysis Constant

An equilibrium constant for a hydrolysis reaction.

Boron Hydrides

Binary compounds of boron and hydrogen.

Natural Radioactivity

Spontaneous decomposition of an atom.

Limiting Reactant

Substance that stoichiometrically limits the amount of product(s) that can be formed.

Electrolytic Cells

Electrochemical cells in which electrical energy causes nospontaneous redox reactions to occur. An electrochemical cell in which chemical reactions are forced to occur by the application of an outside source of electrical energy.

Fast Neutron

A neutron ejected at high kinetic energy in a nuclear reaction.

Specific Gravity

The ratio of the density of a substance to the density of water.

Acyl Group

Compound derived from a carbonic acid by replacing the --OH group with a halogen (X), usually --Cl, general formula is O R--C--X.

Stoichiometry

Description of the quantitative relationships among elements and compounds as they undergo chemical changes.

Beta Particle

Electron emitted from the nucleus when a neuton decays to a proton and an electron.

Zinc

Discovered: known in India and China before 1500 and to the Greeks and Romans before 20 BC as the copper-zinc alloy brass
Origin: The name is derived from the German ‘Zink’.
Atomic no: 30
Mass No: 65
Description: A grey metal with a blue tinge. World production exceeds 7 million tons a year, and it is used to galvanise iron to prevent it rusting. It is also employed in alloys and batteries, and as zinc oxide to stabilise rubber and plastics. Zinc is essential for all living things, and is important for growth and development. The average human body contains about 2.5 grams and takes in about 15 milligrams per day. Some foods have above average levels of zinc, including herring, beef, lamb, sunflower seeds and cheese.

Carcinogen

A substance capable of causing or producing cancer in mammals.