Rust is scientifically called oxidation, which occurs when oxygen comes in long-term contact with certain metals. Over time, the oxygen combines with the metal at an atomic level, forming a new compound called an oxide and weakening the bonds of the metal itself. If the base metal is iron or steel, the resulting rust is properly called iron oxide. Rusted aluminum would be called aluminum oxide, copper forms copper oxide and so on.

The main catalyst for the rusting process is dihydrogen oxide, but we know it better as water. Iron or steel structures may appear solid, but water molecules can easily penetrate the microscopic pits and cracks in any exposed metal. The hydrogen atoms present in water can combine with other elements to form acids, which will eventually cause more metal to be exposed. If sodium is present, as is the case with saltwater, corrosion will likely occur more quickly. Meanwhile, the oxygen atoms combine with metallic atoms to form the destructive oxide compound. As the atoms combine they weaken the metal, making the structure brittle and crumbly.

Some pieces of iron or steel are thick enough to maintain their integrity even if rust forms on the surface. Others are protected by water-resistant paints or other chemical barriers such as oil. The thinner the metal, the better chance rusting will occur. Water alone does not cause steel to rust, but the acidic reaction allows oxygen to attack vulnerable exposed metal. Placing a steel wool pad in water and exposing it to air will cause almost-immediate rusting. The air around the pad will actually feel several degrees warmer. Eventually the individual iron bonds will be destroyed from the heat and the entire pad will disintegrate. Rust formation cannot be stopped easily, but metals can be treated to resist the most damaging effects.

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R­ust is the common name for a very common compound, iron oxide. Iron oxide, the chemical Fe2O3, is common because iron combines very readily with oxygen -- so readily, in fact, that pure iron is only rarely found in nature. Iron (or steel) rusting is an example of corrosion -- an electrochemical process involving an anode (a piece of metal that readily gives up electrons), an electrolyte (a liquid that helps electrons move) and a cathode (a piece of metal that readily accepts electrons). When a piece of metal corrodes, the electrolyte helps provide oxygen to the anode. As oxygen combines with the metal, electrons are liberated. When they flow through the electrolyte to the cathode, the metal of the anode disappears, swept away by the electrical flow or converted into metal cations in a form such as rust.

For iron to become iron oxide, three things are required: iron, water and oxygen. Here's what happens when the three get together:

When a drop of water hits an iron object, two things begin to happen almost immediately. First, the water, a good electrolyte, combines with carbon dioxide in the air to form a weak carbonic acid, an even better electrolyte. As the acid is formed and the iron dissolved, some of the water will begin to break down into its component pieces -- hydrogen and oxygen. The free oxygen and dissolved iron bond into iron oxide, in the process freeing electrons. The electrons liberated from the anode portion of the iron flow to the cathode, which may be a piece of a metal less electrically reactive than iron, or another point on the piece of iron itself.

The chemical compounds found in liquids like acid rain, seawater and the salt-loaded spray from snow-belt roads make them better electrolytes than pure water, allowing their presence to speed the process of rusting on iron and other forms of corrosion on other metals.

http://science.howstuffworks.com/question445.htm

















So you have a nice necklace, wear it in the shower or in the pool, and within a few weeks, that necklace that you once loved is nothing but rust. But have you ever wondered why this happens? By answering some questions, we will develop a greater understanding of what rust is and how it happens and why. An experiment that consists of a few nails being tested for the reaction in the contents of different drinks will give a clearer understanding of why this happens. The obvious question being researched, what is rust?



Chemical contents of ‘Coca Cola’

Chemical contents of ‘V’

Chemical contents of ‘Mother’

Chemical contents

There are many types of contraception methods that are available for men and women who are sexually active but wish to be safe, and protect the risk of pregnancy or infection in some cases. ‘The pill is contraception method that is 98% effective if taken properly’ http://www.thewomens.org.au/ThePill (8/2/10).

The Pill contains two hormones (oestrogen and proestrogen) which stop the ovaries releasing an egg each month. The Pill contains a hormone which changes the mucus at the entrance to the uterus and makes it thicker, so the sperm cannot pass through and fertilise an egg. The pill must be taken for a full seven days before it becomes successful. When the pill is effective, it is really up to the individual to make it successful. ‘Irregular pill taking, vomiting, diarrhoea, and if drugs or other anti-biotic’s are being taken, the pill will become ineffective’ http://www.thewomens.org.au/ThePill (8/2/10). The most dangerous time to miss a pill is towards the middle of the packet.

Some religions believe that a woman has the right to control her own body. Human rights and different religions all have a different opinion on the scenario. In some countries such as China and India, family size has been limited by law or by penalties for large families.

You have to be aware of the benefits and the limitations and disadvantages when considering using the pill as a method of contraception for you. If you do not take the pill as it is directed, it will be less likely to prevent pregnancy. When smoking or taking drugs whilst on the pill, it should be taken into consideration that the pill will not be as effective.

BIBLIOGRAPHY:

http://www.thewomens.org.au/ThePill (8/2/10)

http://www.womhealth.org.au/healthjourney/pill_myths_misconceptions.htm (12/2/10)

http://au.reachout.com/find/articles/the-pill (15/2/10)

http://www.bbc.co.uk/ethics/contraception/mass_birth_control_1.shtml (16/2/10)

http://kidshealth.org.au/teen/sexual_health/contraception/contraception_birth.html (17/2/10)