Tuesday, December 2, 2008

Work Cited

Brown, Theodore. Chemistry: The Central Science. 1st. Chicago IL: Chicago Ink, 2001.
Chemistry. 1st. Chicago: Hawly Publishing, 2006.
Daintith, John. "Radium."Oxford Dictionary of Chemistry. 3. 1999
Edward L. Waterman , Michael S. Matta, Dennis D. Staley,, and Antony C. Wilbraham, . Prentice Hall
Hunt, Andrew. "Strontium Properties."Shaum's A-Z Chemistry. 1st. 2005.
Janice, Smith. "Calcium." Web Elements 26 Nov 2008 .
Strauss, Richard. "Chemical Properties of Calcium."Hawley's Condensed Chemical Dictionary. 2nd. 2006Taylor,Rittens. "Calcium." Web Elements 12/15/2003 24 Nov 2008 .

Monday, December 1, 2008

Strontium

Strontium
Sr
Atomic number: 38
Atomic mass: 87.62 amu
Melting point: 769 degC
Boiling point: 1384 degC
Who discovered it?
Strontium was discovered in the lead mines of a Scottish village named Strontian in 1787. Adair Crawford recognized it as differing from other barium minerals in 1790. Strontium itself was discovered in 1798 by Thomas Charles Hope, and metallic strontium was first isolated by Sir Humphry Davy in 1808 using electrolysis and announced by him in a lecture to the Royal Society on 30th June 1808.
What are its general properties?
Strontium is a grey/silvery metal that is softer than calcium and even more reactive in water, with which strontium reacts on contact to produce strontium hydroxide and hydrogen gas. It burns in air to produce both strontium oxide and strontium nitride, but since it does not react with nitrogen below 380°C it will only form the oxide spontaneously at room temperature.
What are sources for Strontium?
Strontium is found chiefly as celestite and strontianite (both minerals) The metal can be prepared by electrolysis (a method that chemists used to seperate chemically bonded elements and compounds by passing and electrical current through them) of the fused chloride mixed with potassium chloride, or is made by reducing strontium oxide with aluminum in a vacuum at a temperature at which strontium distills off.
What are its uses?
Most of the strontium produced today is used in the manufacture of color television picture tubes. It is also used to refine zinc and is combined with iron to make magnets. (that's right, the very magnets on your fridge! CHEMISTRY INVASION!)
What is its history?
Strontium was discovered by Adair Crawford, an Irish chemist, in 1790 while studying the mineral witherite (BaCO3). When he mixed witherite with hydrochloric acid (HCl) he did not get the results he expected. He assumed that his sample of witherite was contaminated with an unknown mineral, a mineral he named strontianite (SrCO3). Strontium was first isolated by Sir Humphry Davy, an English chemist, in 1808 through the electrolysis of a mixture of strontium chloride (SrCl2) and mercuric oxide (HgO).
Other interesting things
Two strontium compounds, strontium carbonate (SrCO3) and strontium nitrate (Sr(NO3)2), burn with a bright, red flame and are used in fireworks and signal flares. Strontium carbonate is also used to make certain kinds of glass and is the base material for making most other strontium compounds.

Barium
Ba
Atomic number : 56
Melting point: 725 degC
Boiling point: 1640 degC
Density: 3.5
Who discovered it?
Barium was first identified by Carl Scheele in 1774 and was extracted In 1808 by Sir Humphrey Davy, the most celebrated chemist of the 19th century. Sir Humphrey Davy had started experimenting with effects of electricity on chemical compounds. By running an electrical current through a number of substances, Davy was able to isolate metallic elements such as potassium, sodium, mangesium, calcium, and barium. AND THUS BARIUM WAS BORN!
(the studly Sir Humphrey Davy-->)http://upload.wikimedia.org/wikipedia/commons/1/10/Sir_Humphrey_Davy_gravure.jpg

General Properties
Barium is a silvery-white metal that can be found in the environment, where it exists naturally. It occurs combined with other chemicals, such as sulfur, carbon or oxygen. Barium oxidizes in air, reacts vigoroulsy with water to form the hydroxide, liberating hydrogen. Barium reacts with almost all the non-metals, forming often poisouning compounds.

Sources

Barium is only found combined with other elements, primarily in barite or heavy spar (sulfate) and witherite (carbonate).

Uses
Barium's compounds are used in pigments, paints, glassmaking, as weighting compounds, in the manufacture of rubber, in rat poison, and in pyrotechnics (fiya!)

Other Interesting Things
Barium (Greek bary, meaning "heavy") ohh fascinating!

Radium


Radium
Ra
#88
Atomic Mass: 226
Melting Point:700 degC
Boiling Point: 1737 degC
Density:5.0 g/cm cubed
Who discovered it?
Radium was discovered by Pierre and Marie Curie in 1898.
What are some of its general properties?
Its appearance is almost pure white, but it readily oxidizes on exposure to air, turning black.
It is extremley radioactive and reacts violently with water and oil to form radium hydroxide
In radium preperations, emmited radiation consists of three types of radiations:alpha particles, beta partciles, and gamma rays. The fire from Radium compounds produces a bright red flame. Due to its geologically short half life and intense radioactivity, radium compounds are quite rare, occurring almost exclusively in uranium ores.
What are the sources of Radium
Radium was discovered in pitchblende or uraninite. Radium is found in all uranium minerals.There is approximately 1 gram of radium for each 7 tons of pitchblende.(pitchblende is a radioactive, uranium-rich mineral and ore with a chemical composition)
What are some historical points for Radium?
Radium was initially used in selft-luminous paints for watches, nuclear panels, aircraft switches, clocks, and instrument dials. Once the adverse affects of radioactivitey were becoming more commonplace, the useage of radium in paints declined. Radium was also once used in products like toothpaste, hair creams, and even food items due to its supposed curative powers. Because of Ra letha qualities, putting it in digestable items didn't work out too hotly...D:
Other intersting things
Radium is highly radioactive and its decay product, radon gas, is also radioactive. Since radium is chemically similar to calcium, it has the potential to cause great harm by replacing it in bones. Inhalation, injection, ingestion or body exposure to radium can cause cancer and other disorders. Stored radium should be ventilated to prevent accumulation of radon

Calcium

CALCIUM ( from the latin word calcis - meaning " lime")
How Did this Wonderful Element come to be!?
The Romans prepared lime (called calx) in the first century but it wasn't until Sir Humphrey Davy isolated it as a metal in 1808 A.D that it came to be!
CA
#20
Atomic mass: 40.078 amu
Melting Point: 839.0 °C ( 1542.2 °F)
Boiling Point: 1484.0 °C ( 2703.2 °F)
Fifth mosst abundant element in the Earth's crust!
You've known this element for as long as you remember, its the reason why you hated grown ups ( "Drink your milk or Jimmy, you'll just have to drink water from a dish like the puppy") But hey, familiarity is always so comforting right?- but like an old blanket that starts to unravel you figure out that there was, and is, more to it than same ol' same ol'. Meet Calcium your bones, your mothers bones, coral reefs, your dog and your new bffl.( best friend for life!)
Reaquant yourself with an old friend
Properties:
-Grey silvery
-relatively soft metal!
-It reacts with water and the metal burns with a yellow-red flame
(It readily forms a white coating of calcium nitride (Ca3N2) in air!!)http://www.youtube.com/watch?v=puEc5YE-YJ0
-( does not occur as a free element in nature)
CALCIUM EXSISTS INSIDE YOU!
Uses of calicum are extremely evident without it you would be , well, not very coordinated- or good looking. Your structure and the structure of animals ( don't forget animal shells like muscles!) Are all made out of calcium( there was a methodology after all -milk keeps your bones strong LISTEN TO YO MAMA!)