Cyanide

Ask your students to name you a poison and probably the first one that they mention will be Cyanide. The will probably have come across this substance watching World War II or James Bond movies. This aside, what do they really know about Cyanide? Image kindly reproduced according to the licence found here. Cyanides contain the cyano group CN-. There is a triple bond between the carbon and nitrogen and the negative charge is centred on the carbon atom. In organic compounds ...

Why does it smell so bad?

This is not directly IB related but it is certainly Chemistry related. I was carrying out the reaction between iron filings and hydrochloric acid yesterday. An experiment I am sure many others out there have carried out. The context is the reactivity series and it also involved reacting magnesium, aluminium, copper and zinc with hydrochloric acid. I have carried out these reactions many times in many different schools and continents and always get the same puzzling result. The iron reacts (fine) butr ...

New Ammoina

Nitrogen is often considered an inert gas - it has a very high bond energy, so much energy is needed to overcome this strong  triple bond. Nitrogen is useful to us. Nitrogen containing compounds are used to make fertilizers, explosives and is found in every pharmacological drug. 80% of the air is made from the stuff but in order to use it we must first make it into ammonia (NH3) via the Haber - Bosch process. The Haber - Bosch process needs high temperatures (typically ...

Electrolysis saves the day

The Cutty Sark is a 19th Century Clipper ship. Built in 1869 to transport tea, the ship was built at a time when iron hulled ships were beginning to replace wooden ships. The Cutty Sark has a wooden hull fixed to a metal frame. For the past 50 years of so, the Cutty Sark has been kept alongside the River Thames in London in dry dock. However, every time it rains, the integrity of the ship was threatened (and believe me, ...

Iron and its removal of Carbon Dioxide

  Iron fertilization. This is the name given to the process where iron filings are intentionally sprayed (or added) to the ocean. By NOAA MESA Project (http://www.photolib.noaa.gov/bigs/fish1880.jpg ) , via Wikimedia CommonsWhy? The idea is that the iron, stimulates the growth of plankton, that in term removes CO2 from the atmosphere. The good news? It actually works. Plankton does absorb CO2. When it dies, it sinks to the bottom of the ocean, taking the carbon with it. The bad news? The amount of carbon ...

Toxic Sludge

  What have Iron Oxide, Aluminium Oxide, Silicon Dioxide, Titanium Dioxide and Sodium Oxide all got in common? Well, they were the substances found in the highest concentrations in the recent toxic sludge spill in Hungary. What effect will they have? It seems open to debate at ther moment but you can read more here: http://www.bbc.co.uk/news/world-europe-11492387

Gemstones

  Gemstones are all broadly fromed in the same way - a liquid containing dissolved chemicals cools and crystals grow! However, the devil is in the detail..... ....Firstly, extreme pressure is also needed. Gemstones are rare becuae the correct chemicals need to be present in large enough quantities. Rubies and sapphires are essentially made from aluminium oxide. The red colour of ruby comes from traces of chromium. Sapphires colour comes from other elements, for example titanium or iron. Both rubies and sapphires also contain some magnesium ...

The Earliest Periodic Table?

Around 1400BC in Anatolia (essentially Turkey), Iron was extracted. This became the seventh metal to be discovered. The metals were grouped as follows, with the idea that metals matured in the earth, beginning with dull lead and ending with shiny gold. It was the start of alchemy.... The seven metals became linked with the seven days of the week: Metal Planet Day Gold Sun Sunday Silver Moon Monday Mercury Mercury Tuesday Copper Venus Wednesday Iron Mars Thursday Tin Jupiter Friday Lead Saturn Saturday The ideas behind this article were taken from ‘The Elements’ by Philip Ball ISBN 0-19-284099-1

Iron (Fe)

  Iron is essential to all living things but in large quantities can be toxic - possibly leading to liver and kidney damage.   However, we need Iron for our blood - to form haemaglobin and carry oxygen. Males need 7mg daily and females 11mg but only 25% of what is in food is actually absorbed. It is estimated that 500 million people are anaemic through lack of Iron. Click here to see more: http://www.periodicvideos.com/videos/026.htm It is also the heaviest element that can be made ...