Star InactiveStar InactiveStar InactiveStar InactiveStar Inactive
 

The percent of a specified compound or element in an impure sample.

Latest Articles

  • 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?

  • 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...

  • 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...

  • Ozone

    We breathe 24 hours a day, 7 days a week, consuming about 25 kg of air every day. It turns out that we practically predetermine our health by the air we breathe.

  • 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

Saponification

Hydrolysis of esters in the presence of strong soluable bases.

Dispersing Medium

The solvent-like phase in a colloid.

Excited State

Any state other than the ground state of an atom or molecule.

Saccharic acid

A white, needlelike, crystalline, water-soluble solid or syrup, C6H10O8, usually made by the oxidation of cane sugar, glucose, or starch by nitric acid. Also called "Glucaric acid."

Line Spectrum

An atomic emission or absorption spectrum.

xenon tetrafluoride

A colorless, crystalline compound, XeF4, prepared by heating a gaseous mixture of fluorine and xenon.

Hydrogenation

The reaction in which hydrogen adds across a double or triple bond.

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 the stage, with the illuminator below that.

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.

Lone Pair

Pair of electrons residing on one atom and not shared by other atoms, unshared pair.