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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The Hills Are Alive With…
Sound travels as waves at about 340 m/s in air and if you can’t remember some of the terminology about waves you might look here at a previous post. You could also look at this excellent page to play with an animation exploring amplitude, frequency and wavelength. (Don’t forget that you can also use the …
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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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Incontinentia Buttocks…
Re-reading a post from last term on diffusion and smell inevitably made me think about flatulence. Flatulence is the polite word for farting. Apart from Her Late Majesty the Queen, everybody suffers from flatulence from time to time. Flatus (a Latin word I believe) refers to gases produced in the gut although a hefty proportion …
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Gold Part Two…
[This is follow up to Gold Part One.] A pupil asked… Will the earth naturally produce more gold for us to extract? How long will this take? How long is the half-life of gold and what does it decompose into? Would it be possible to industrially produce gold from different atoms? A. Pupil Esq. When …
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Nuclear Fusion…
At a laboratory in California, in what is called the National Ignition Facility, is the largest collection of giant lasers in the world. Their aim is to produce sustainable nuclear fusion similar to that happening in the Sun. The nuclear power stations we currently have split large atoms (such as Uranium) in a process called …
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Eliomys quercinus…
As I sipped my coffee this morning, I watched a mother garden dormouse (Eliomys quercinus) attempting to carry one of her young up to her nest in the eves of my house. She wedged herself between the wall and a drain pipe and scrambled upwards with the pup squeaking loudly.It had rained over night and the …
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