I do love a snappy post title! Air contains lots of moisture. It can be as much as 30 g of water in every 1 m3 of air. If you dry the air (by passing it over a chemical that reacts with water) then the mixture remaining is slightly more than 20% oxygen. You can …
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Category:Chemistry
Galvanised Into Action…
This is another post in the Rusting Series. Please make sure that you have read the others if you are here revising for upcoming exams – otherwise just relax and absorb. Many metals corrode over time; they become weaker as they react with their environment and often eventually break, crumble or otherwise fail. Iron (steel) …
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Lithium…
Lithium is the third element on the periodic table and first metal. It sits in Group I with the other reactive metals such as sodium and potassium. It is soft, low density and highly reactive – although the least so of the alkali metals. Apparently they used to put lithium citrate into 7-Up although they no …
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Rates Of Reaction…
A chemical reaction involves reactants turning into products. You can tell when a reaction has happened because there will be production (or sometimes absorption) of energy; usually in the form of heat but sometimes light & sound too. There may also be a change of colour but this doesn’t always happen. The end products will …
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Copper…
After iron and aluminium, copper is probably the third most important industrial metal. It is used in electrical wiring and for printed circuit boards (PCB). The board is completely coated in copper then copper is etched away to leave the path that the electricity needs to follow. Copper is also used for plumbing although it is …
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Conservation Of Mass…
When a chemical reaction occurs, mass/matter is conserved. This means that the reactants and the products have the same mass. No new atoms are created during the reaction and no atoms are destroyed; they are just rearranged. The following short video attempts to illustrate this principle and although it contains a rather big mistake, it …
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What Have The Romans Ever Done For Us…
Work done by Dr Nikola Koepke (formerly from Oxford University but now at Zurich Universtory) looked at the remains of skeletons from the 8th century BC until the 18th century AD and used changes in people’s heights over this period as a measure of how well fed they were. The study combined biology and archaeology …
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Sacrificial Protection…
Steel is an alloy of iron containing other elements to improve its physical properties. Mild steel is iron with about 0.25% carbon added; stainless steel is iron with chromium and nickel added to reduce rusting. Iron will rust whenever it comes into contact with both water and oxygen. If you can stop one of those …
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Blast Furnace…
Iron is extracted from its ore (rocks rich in iron oxide) in a blast furnace. The iron ore is mixed with coke (a refined form of coal with a very high carbon content) and limestone. This mixture is baked into a crusty mixture known as sinter (that has a very high surface area) before being …
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Rusty Hinge…
Iron, even in the form of steel, is prone to rust. This is a slow reaction that takes place when the iron is in contact with both water and oxygen. It is quite easy to show that water and oxygen are both needed for rusting by setting up a simple controlled experiment. Things you need …
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