Oxygen: December 2009

OXYgeN - The most abundant element on Earth's surface

BASIC FACTS ABOUT THE ELEMENT OXYGEN

Symbol: O
Atomic #: 8
Mass #: 15.9994
# of protons in an oxygen atom: 8
# of Neutrons in an oxygen atom: 8
# of electrons in an oxygen atom: 8
Charge of an oxygen ion: -2
Physical Properties: Oxygen gas is colourless, odourless, and tasteless. The liquid and solid forms are a pale blue color and are strongly paramagnetic. It's crystal structure is cubic.
Chemical Properties: Oxygen supports combustion, combines with most elements creating oxides, and is a component of hundreds of thousands of organic compounds. Ozone (O3), a highly active compound is formed by the action of an electrical discharge or ultraviolet light on oxygen.
Melting Point: 50.5K -222.65°C -368.77°F
Boiling Point: 90.33K -182.82°C -297.08°F
The following video explains about ozone, oxygen's reactivity, and its paramagnetism.

Word Origin: "Oxygen" comes from the Greek words "oxys" (acid) and "genes" (former) and means "acid former".

BOHR-RUTHERFORD DIAGRAM OF THE ELEMENT OXYGEN

USES OF THE ELEMENT OXYGEN

-Breathing. A person can survive a few days without food or water, but no more than a few minutes without oxygen. In the absence of oxygen, energy-generating chemical reactions within cells would come to an end, and a person dies.
-Cellular Respiration. Glucose and oxygen are needed to produce energy, carbon and water.
-Medicine. Sometimes patients must be given oxygen therapy to stay alive.-Converting metals. For example, in the processing of iron ore in a blast furnace, oxygen is used to convert carbon to carbon monoxide.
-Welding. The two most common welding torches make use of the reaction between oxygen and hydrogen, or between oxygen and acetylene.
-Combustion. Oxygen is part of the Fire Triangle. When added to heat and fuel, it will combust.
-Sewage treatment. Oxygen is pumped through water to increase the rate at which naturally occuring bacteria break down organic waste materials.

DISCOVERY OF THE ELEMENT OXYGEN

Oxygen was discovered for the first time by Carl Wilhelm Scheele, in 1772. Joseph Priestly independently discovered oxygen in 1774 and published his findings the same year, three years before Scheele published. Antoine Lavoisier also discovered oxygen in 1775, was the first to recognize it as an element, and coined its name "oxygen". There is a historic dispute about who discovered oxygen. Most credit Priestly alone or Both Priestly and Scheele. Here is a brief summary of their lives related to oxygen.

Carl Wilhelm Scheele

Birth: December 9, 1742
Death: May 21, 1786
Nationality: German-Swedish
Occupations: He was an apprentice since he was fourteen-years-old for eight years before becoming an apothecary's clerk.
How the element oxygen was discovered: Beforing studying oxygen Scheele studied air. He found that air was a mixture of "fire air" and "foul air" which means it is a mixture of two gases. He found that oxygen was the combustible gas.
Other accomplishments: Discovered molybdenum, tungsten, and chlorine

Joseph Priestley

Birth: March 13, 1733
Death: February 6, 1804
Nationality: English
Occupations: Theologian, clergyman, natural philosopher, educator, and political theorist.How the element oxygen was discovered: Priestleyput a sprig of mint into a transparent closed space with a candle that burned out the air until it soon went out. After 27 days, he relit the extinguished candle again and it burned perfectly well in the air that previously would not support it. And how did Priestley light the candle if it was placed in a closed space? He focused sun light beams with a mirror onto the candle wick (Priestley had no bright source of light, and had to rely on the sun). Today, of course, we can use more sophisticated methods to light the candle like focusing light from a flood light through converging lens, or by an electrical spark.So priestly proved that plants somehow change the composition of the air. In another celebrated Experiment from 1772, Priestley kept a mouse in a jar of air until it collapsed. He found that a mouse kept with a plant would survive. These kinds of observations led Priestley to offer an interesting hypothesis that plants restore to the air whatever breathing animals and burning candles remove - what was later coined by Lavoisier "oxygen".
Other accomplishments: Many other gasses and he invented carbonated beverages (soda water) and the pencil eraser. He also had a great impact on the Unitartian movemement. He wrote over 150 works. His influence may be why most credit only Priestley for discovering oxygen.

Antoine Lavoisier

Birth: August 26, 1743
Death: May 8, 1794
Nationality: French
Occupations: Lavoisier was a noble prominent in the histories of chemistry and biology.
How the element oxygen was discovered: He didn't discover oxygen but he recognized and named it.
Other accomplishments: He also recognized and named hydrogen. He stated the first version of the law of conservation of mass, abolished the phlogiston theory, helped construct the metric system, wrote the first extensive list of elements, and helped to reform chemical nomenclature. He discovered that, although matter may change its form or shape, its mass always remains the same. He conducted many experiments in biology and chemistry.

Interesting Facts about the Element Oxygen

-Oxygen forms chemical bonds with almost all other elements, creating the corresponding oxides. For example, rust is actually the formation of iron oxide (Fe2O3) and Lime is actually calcium oxide (CaO).

-Oxygen on Earth actually usually exists in the form of O2 called dioxygen, but also exists as O3, ozone, mostly in the atmosphere but also exists on the surface in smog.

-The O3 in our atmosphere helps to protect the Earth from UV rays from the Sun. If the UV rays we’re able to pass through the atmosphere unhindered, life would not be able to survive. Ironically O3 on the surface is harmful to animal lung tissue.

-Oxygen is the 3rd most abundant element by mass in the Universe, behind Hydrogen and Helium, and the most abundant element by mass in the Earth’s crust.

-O2, in liquid form and in the presence of a magnetic field, forms a magnet and has been shown to be able to form a bridge, between the two poles of a magnet, capable of supporting its own weight.

-Aside from being one of the two elements that bond to form water (H2O), oxygen also dissolves into water, which is the oxygen that fish and other creatures breathe.

- At the present rate of creation, by photosynthesis, and consumption, by respiration and decay, the entire Earth’s oxygen is renewed every 2000 years.

-Humans inhale more than 6 billion tones of oxygen each year.