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Trapping of heat at the surface of the earth by carbon dioxide and water vapour in the atmosphere.

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...

  • 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...

  • Creating Malachite egg

    One of the most interesting and obvious chemical experiments is the experiment on the interaction of copper sulfate and calcium carbonate. The latter is contained in the shell of a simple egg, but copper sulphate should be searched in a chemical reagent store. This experience is simple, but...

  • Varieties of garnet minerals

    The most famous type of garnet stone is pyrope (flaming). This is the "oldest of garnets", with a dense red color, similar to the grain of an edible garnet. Pyrope has a variety called rhodolite - a stone of dense pink or pink-purple color, which sometimes has the alexandrite effect and is used in...



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Flammable

A liquid as defined by NFPD and DOT as having a flash point below 37.8°C (100°F).

Atmosphere

A unit of pressure, the pressure that will support a column of mercury 760 mm high at 0 °C.

Heavy Water

Water containing deuterium, a heavy isotope of hydrogen.

Charle's Law

At constant pressure the volume occupied by a definite mass of gas is directly proportional to its absolute temperature.

Buret

A piece of volumetric glassware, usually graduated in 0.1-mL intervals, that is used to deliver solutions to be used in titrations in a quantitative (dropwise) manner.

Percent Composition

The mass percent of each element in a compound.

Photochemical Oxidants

Photochemically produced oxidizing agents capable of causing damage to plants and animals.

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.

Voltage

Potential difference between two electrodes, a measure of the chemical potential for a redox reaction to occur.

Halogens

Group VIIA elements: F, Cl, Br, I