Star InactiveStar InactiveStar InactiveStar InactiveStar Inactive
 

Group of atoms remaining after a hydrogen atom is removed from the aromatic system.

Latest Articles

  • The most expensive metal in the world

    Do you think the most expensive metal is gold? No! On earth there are more valuable metals. But we need to divide the value of metals that occur in nature, and metals - isotopes, which are obtained in special laboratories. Let’s look at natural metals first.

  • 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...

  • Interesting facts about metals

    Metals have been used by people since ancient times. All the time the process of obtaining them was improved, useful alloys of various metals appeared. Let’s look at interesting facts about metals.

  • Chemistry of the sky

    Chemistry can teach us about the composition of celestial bodies and determine their age.

  • Why do copper products change color, and what is the name of the process?

    Probably, every person wants to know, why over time the copper turns green and becomes bloomed. This is easy to explain: that film is called patina.



Most Popular

Electronic Transition

The transfer of an electron from one energy level to another.

Lanthanides

Elements 58 to 71 (after lanthanum).

Density

Density is the ratio b/w Mass and Volume: D=M/V

Ester

A Compound of the general formula R-C-O-R1 where R and R1 may be the same or different, and may be either aliphatic or aromatic.

Bronsted-Lowry Acid

A proton donor.

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.

Strong Electrolyte

A substance that conducts electricity well in a dilute aqueous solution.

 

Alloying

Mixing of metal with other substances (usually other metals) to modify its properties.

Fast Neutron

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

Stereoisomers

Isomers that differ only in the way that atoms are oriented in space, consist of geometrical and optical isomers.