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Happy 150th anniversary for periodicity


A new image for the 150 year old table

It’s the 150th anniversary of the periodic table of chemical elements – a pinnacle of the scientific method and an explanation of the world around us that has stood the test of time. The picture is a view of the table that you may not have seen. It looks far from the well organised version in the textbooks. In fact the size of each element reflects its relative abundance on the Earth whilst the order remains as the original table – atomic number. In parallel with the loss of wildlife and habitat, we are also have endangered elements! Well, you might say, many have difficult names and you are never likely to see most of them. However, you might not be aware of the value of some of these rare elements.

Helium is rare on Earth, but the second most common element in the Universe. It is so light that we use it to fill balloons and watch them float away – as does natural helium, which is why we collect it from trapped gas under the surface of the Earth. It does have more important uses, being used in the manufacture of mobile phones and without it MRI scanners in hospitals could not work. Helium also has strange properties. It's the only material that never becomes solid – remaining a liquid at absolute zero. As a superfluid it flows frictionless and so can leak out of vessels through microscopic cracks or even flow up and out of a beaker. This can all be explained by quantum mechanics, but unlike many of the counter-intuitive ideas of this theory, you can see the weird behaviour of a superfluid with your own eyes.

Gallium is a strange glittering metal widely used in electronics, but it is also beloved by magicians as it melts at slightly over room temperature so a spoon made from the metal will ‘disappear’ in a cup of tea or even melt in the hand.

Dysprosium is named after the ancient Greek dysprositos, meaning "hard to get". It is used in electric motors and notably in wind turbines – so the green economy is dependant on this element.

Lithium is also much in demand for batteries for computer notebooks amongst other things. The latest technology allows a large battery to take electricity from the National Grid during the night and store it for use in the day when its more expensive to use direct. Tesla installed a 100-megawatt battery in South Australia to solve their demand problems. This battery can store enough to power 30,000 homes for 1 hour. The battery is connected to a wind farm. America, the UK and New Zealand also use battery technology to manage power supplies. The current world supply of Lithium will permit 2 million 16 kWh batteries to be made per year. In 2017, some 73.5 million cars were produced worldwide.

Arsenic is one of the geological copper family: copper, arsenic, selenium, silver, tellurium and gold. All six are technologically important. Arsenic is used for the production of high speed computer chips and is a problem because there is little interest in mining such a poisonous material. Budding Agatha Christie writers please note they may need to find another suitable poison. In researching this article I discovered that Beryllium is extremely toxic and also causes lung cancer, although the mechanism is not known. Beryllium compounds may stay in the soil for thousands of years. Disposal of coal ash, incinerator ash, and industrial wastes may increase the amount of beryllium in the soil and the burning of coal and oil means levels are higher in cities. In the copper family Gold production is also problematic. 'The element occurs at such low concentrations in the ore that mining and processing has the potential to cause significant amounts of air and water pollution, so it has the most severe environmental implications ranking'.

Yttrium was discovered in 1794, but you’ve probably never heard of it. It increases the strength of aluminium and magnesium alloys. It is also used in radar, in white LED lights nd camera lenses. Yttrium oxysulfide used to be widely used to produce red phosphors for old-style colour television tubes, but don’t worry because europium is now used and is a much brighter red. Yttrium-90 has medical uses as it can be used to treat some cancers, such as liver cancer.

Cut open any electrical wire and you will see the wonderful reddish colour of copper, which in the UK is the latest fashionable material for home furnishings. There have been no major discoveries of copper ore in the last two decades. Fully electric vehicles require four times as much copper as cars that run on combustion engines. Currently there are 1 million electric cars out of a global fleet of closer to 1.1 billion. As the Americans say – you do the maths.

You may not need to worry as Aluminum is the most common alternative to copper for electrical wiring. Before the invention of the Hall-Heroult refining process, Aluminium cost about the same as silver. Although it makes up 8% of the earth’s surface, it took 18 years after its discovery to purify enough of the element to study it. Napoleon III though it would be useful as lightweight armour but eventually had his supply of aluminium melted down and pressed into cutlery. He was rumoured to have eaten off of the aluminium plates while his guests had to make do with gold plates.

The disadvantages of aluminium over copper are higher resistance, so the wire gauge will need to be thicker and more electric power will be used. Its softer and reacts with more materials so terminals (in plugs) will need to be modified to use different materials. Worldwide production of aluminium in 2010 was 41.4 million tonnes. Around 600 billion kilowatt hours of electrical energy were used in the production of aluminium. The total world production of electrical energy is about 20,000 billion kilowatt hours, so this means that more than 3% of the world’s entire electrical supply went to extraction of aluminium. You remember Australia and its power supply problems? Australia uses about 12% of its electricity to make Aluminium. Australia is the world’s fourth largest aluminium producer. The red colour of Australia’s deserts comes in a large part from the presence of bauxite from which the metal is extracted.

A famous book was published just as I was going to University called ‘The Limits to Growth’. You can read it here https://www.clubofrome.org/report/the-limits-to-growth/ . This webpage says: ‘The message of this book still holds today: The earth’s interlocking resources – the global system of nature in which we all live – probably cannot support present rates of economic and population growth much beyond the year 2100, if that long, even with advanced technology.’

No wonder China is interested in mining the Moon. However, that may not be the whole solution. In spite of many years highlighting the destruction of the tropical forests around the world and the impact that is having on our lives now and in the future, the loss continues. I saw this program recently https://www.bbc.co.uk/iplayer/episode/b09qjlfs/chris-packham-in-search-of-the-lost-girl in which Chris Packham searches for a nomadic tribe he photographed 20 years ago in Sumatra (that’s where orangutans are found – in 2015 only 7000 remain there). He finds some of the tribe in a palm oil plantation living and earning a wage within it. When he visited them before they had all their needs supplied by the forest, but now they are dependant on the palm oil company. 45% of land in Southeast Asia currently used for palm oil production had been forest back in 1990. Palm oil represents around 1/3rd of the edible oils produced and is widely used in processed food and for the production of bio-diesel fuel.

The following article defends the palm oil industry saying that agriculture is the reason that so much forest is destroyed in South East Asia https://phys.org/news/2017-06-palm-oil-responsible-global-deforestation.html. Whatever the reason its clear to me that the world is living far beyond its means (and of course the majority actually exist in poverty!). What it will take to bring us all to our senses, I wonder, but of course there are more important things to worry about like Brexit – aren’t there?

On a different subject I see that 70% of children are allowed to take their smartphones to bed with them and many do not have time to physically meet their friends any more! Of course this may be part of the economic solution since they will not need to drive anywhere when they grow up.

I had someone send me a message to say that he could not spend an hour driving to meet our East Sussex Naturists social group, even though he wanted to be a member of our Facebook group – in case there might be a more interesting event to attend. Could he perhaps mean that he would attend an event where he didn’t have to meet anyone?!

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