We use cookies to give you the best experience possible. By continuing we’ll assume you’re on board with our cookie policy

Maagang Pagbubuntis

The whole doc is available only for registered users
  • Pages: 2
  • Word count: 389
  • Category: Chemistry

A limited time offer! Get a custom sample essay written according to your requirements urgent 3h delivery guaranteed

Order Now

Compounds of boron, notably borax, have been known since early times, but the pure element was first prepared in 1808 by the French chemists Joseph Gay-Lussac and Baron Louis Thénard, and independently by the British chemist Sir Humphry Davy. It is a trace element needed for plant growth, but toxic in excess. Research suggests that it is also nutritionally important for bone health in humans and other vertebrates.

Pure boron, as usually prepared, is a powder, though a crystalline form can be prepared by dissolving boron in molten aluminium and cooling slowly. The atomic weight of boron is 10.81; the element melts at about 2180° C (3956° F), boils at about 3650° C (6602° F), and has a relative density of 2.35.

Boron does not react with water or hydrochloric acid and is unaffected by air at ordinary temperatures. At red heat it combines directly with nitrogen to form boron nitride (BN), and with oxygen to form boron oxide (B2O 3). With metals it forms borides, such as magnesium boride (Mg3 B2). The original sources of boron compounds were the minerals borax and boric acid. More recently, important boron ores have been, in the United States, ulexite (NaCaB5O9· 8H2O), colemanite (Ca2B6O11· 5H 2O), and kernite (Na2B4O7· 4H2 O); and in Germany, boracite (Mg7Cl2B16O 30). Boron ranks about 38th in natural abundance among the elements in the Earth’s crust.

Although boron has a valence of 3 and its position in the periodic table would indicate a close relationship to aluminium, it is actually much more like carbon and silicon in chemical properties. In its compounds, boron acts like a non-metal, but unlike most non-metals, pure boron is an electrical conductor, like the metals and like carbon (graphite). Crystalline boron is similar to diamond in appearance and optical properties, and is almost as hard as diamond. Most extraordinary in their anomalous similarity to the compounds of silicon and carbon are the boron hydrides. The boron compounds of industrial importance include borax (Na2 B4O7· 10H20), boric acid (H3BO 3), and boron carbide (B4C).

Boron has several important applications in the field of nuclear energy. It is used in particle detectors and, because of its high absorption of neutrons, it is employed as a control absorber in nuclear reactors and as a constituent material of neutron shields.

Related Topics

We can write a custom essay

According to Your Specific Requirements

Order an essay
Materials Daily
100,000+ Subjects
2000+ Topics
Free Plagiarism
All Materials
are Cataloged Well

Sorry, but copying text is forbidden on this website. If you need this or any other sample, we can send it to you via email.

By clicking "SEND", you agree to our terms of service and privacy policy. We'll occasionally send you account related and promo emails.
Sorry, but only registered users have full access

How about getting this access

Your Answer Is Very Helpful For Us
Thank You A Lot!


Emma Taylor


Hi there!
Would you like to get such a paper?
How about getting a customized one?

Can't find What you were Looking for?

Get access to our huge, continuously updated knowledge base

The next update will be in:
14 : 59 : 59