An endothermic reaction is one that gets colder as it proceeds; unlike an exothermic reaction which releases heat as it progresses. It all depends upon the bonds between the atoms in the reactants and the products. The first thing to say is that during a chemical reaction, exactly the same atoms appear in the products …
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Solubility…
A solution is a mixture between a solvent and a solute. The solvent is the liquid in which something dissolves and the solute is the substance dissolved in the solvent. In salt solution, water is the solvent and salt is the solute. Things can be encouraged to dissolve in water by stirring the mixture to …
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A Great Chemistry Video
This is a 15 minute chemistry demonstration video from a TEDx talk in Newcastle. It is a longer watch but worth every second. The professor has to do 25 demonstrations in the 15 minutes available – will he manage it in the time? Questions…
Aluminium…
You should read the (very slightly eccentric) post from a few years ago – Foiled Again. It might also be worthwhile checking the other posts in the series – Elements. Aluminium is the most abundant metal element in the Earth’s crust. Despite this, no known plant or animal uses aluminium compounds to perform any biological …
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Condensation…
When water vapour meets the glass of a beaker containing cold water or ice it condenses into a liquid, forming droplets of water on the outside of the glass. If you heat a beaker of water with a Bunsen flame, water vapour produced by the flame initially condenses on the cold surface of the beaker. …
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Alkalis…
8E & 8D A base will react with an acid to produce a salt and water. If the base dissolves in water we call it an alkali. Alkalis are slimy to the touch, taste bitter (or soapy) and turn litmus blue. Alkalis have a pH greater than 7. All metal oxides are bases and metal …
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Types Of Reaction…
I posted this video a few years ago – it is rather crackly but it does explain things nicely. It describes several different kinds of reaction. The first sort it mentions is “synthesis” reactions – this is what we have been calling combination reactions. The only one that might be new is “double displacement” but if …
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The Elements…
. You can try your hand at this quiz that tests your knowledge of all the symbols and elements. It is not easy but you can customise it by clicking on ‘More options please’ and telling it which elements you want included. You should know the first 20 but try to include a few others …
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Salty Lamps…
In the 80s my parents bought an ioniser for my brother’s room because we had read that negative ions discouraged the release of serotonin in the brain and could also help to reduce asthma. This was before the Internet so we couldn’t spend five minutes researching the claim before buying one. It was a scientific claim …
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Even More Good Carbon News…
In 2009 I wrote a post called Good Carbon News about graphene; an allotrope of carbon. Allotrope means an element in more than one physical form e.g. carbon can be in the form of graphite, diamond or graphene. I go into more detail in the 2009 article which is worth a read. Graphene is in …
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