A Tea Time Quiz - Ten Elemental 'T's

Answer: Titanium

Titanium, which has the chemical symbol Ti and atomic number 22, was first discovered in 1729 in Cornwall, England but not fully identified until 1795 when it was named after the Titans from Greek mythology. Its key properties are that it is both very light and very strong, which makes it ideal for use in both the aerospace and automotive industries. Most planes - military and commercial - will contain a fair bit of titanium in both the structure itself and the engines, while the engines, gearboxes and even the skid plates of Formula 1 racing cars have been made of titanium or its alloys.

Despite being one of the most abundant metallic elements on Earth, titanium tends to be quite expensive. This is because pure titanium is not found naturally and has to be produced using lengthy and costly techniques such as the Kroll Process.

Answer: Terbium

Terbium is one of four elements named after the Swedish village of Ytterby - the others being Erbium, Ytterbium and Yttrium. Terbium has the atomic number 65, the chemical symbol Tb, and was first discovered in 1843. It is a member of the lanthanide series, which are also known as the rare earth elements although most of them - including terbium - are not particularly rare. Terbium is used in electronic devices, fuel cells and trichromatic lighting.

Period 6 is the term given to the sixth row of the periodic table, which includes the lanthanides despite the fact that they are often shown below the main part of the table in a section known as the f-block. Reading across the periodic table from left to right, each subsequent element in the same period has one more proton than its predecessor and therefore its atomic number is one higher.

Answer: Tungsten

Tungsten, otherwise known as wolfram, is not just notable for having the highest melting point of all the elements, but also for its hardness, tensile strength and malleability - which, combined, make it an extremely useful substance. Tungsten is mined in many countries around the world and used in a wide range of different applications. It is found in light bulbs and electronics; can be made into jewellery; is used in the cutting edges of knives, drills and saws; forms ballast for aircraft, yachts and racing cars; and is even involved in the process of making depleted uranium!

The name tungsten comes from the Swedish for 'heavy stone', while wolfram is somewhat more imaginatively derived from the German for 'wolf cream'.

Answer: Thorium

Like all elements of the actinide series, Thorium is radioactive. It is a naturally occurring metallic element that was named after Thor, the Norse God of thunder, by Jöns Jacob Berzelius, a 19th century chemist often referred to as the "Father of Swedish Chemistry". Although Berzelius was responsible for isolating and identifying thorium from thorite ore, the ore itself was discovered by a Norwegian priest (and amateur mineralogist) by the name of Hans Morten Thrane Esmark.

Despite its radioactivity, thorium has several commercial applications and can be found in lenses (for both cameras and scientific equipment), gas and oil powered lamps, electronic equipment and microwave ovens.

Answer: Thallium

Thallium was first discovered in 1829 by William Crookes and Claude-Auguste Lamy (who worked independently but came up with the same findings). Despite being widely used in electronics and glass manufacturing (and even occasionally in the pharmaceutical industry), thallium is highly toxic and a fatal dose can be received by either inhalation, ingestion or simply from contact with the skin or eye. The key symptoms of thallium poisoning are nerve damage and hair loss - the latter of which unfortunately led to its use in depilatory products prior to the extent of its toxicity being discovered.

William Crookes named thallium after the Greek word 'thallos', meaning 'a green shoot'. This comes from the fact that thallium has a distinctively green spectral line.

Answer: Thulium

Given the number of chemical elements that begin with 'T' and end in 'ium', noting that Thulium has the chemical symbol Tm may not have been the most obvious clue for non-scientists. Its value comes from the fact that it is rare - pure thulium is not found naturally and must be separated from its various ores by techniques such as ion-exchange or solvent-extraction.

Thulium is named after Thule, the Ancient Greek name for Scandinavia and Iceland. Despite this fact, the majority of the world's thulium reserves are believed to be in China, with significant levels also present in Australia, Brazil, India and the USA.

Answer: Technetium

As its name might suggest, technetium is not generally found naturally in the environment and significant quantities can only be obtained synthetically. Most technetium available is a by-product of the nuclear fission of various uranium and plutonium isotopes. It can be extracted from spent fuel rods from nuclear reactors or obtained by exploding a nuclear bomb and sifting it out of the fallout. Although neither option is particularly environmentally friendly, the former is probably preferable!

Technetium is used in medicine as a radioactive tracer in diagnostic tests of various organs including the brain, heart and liver, as well as in blood tests and assessments of tumours. In particular this industry uses the nuclear isomer technetium-99m, which has a half-life of around six hours and turns into the isotope technetium-99.

Answer: Tantalum

Tantalum occurs naturally in various ores along with niobium, an element that was often confused with tantalum in the early 19th century. Ores containing more tantalum than niobium are generally called tantalite, while ores containing more niobium than tantalum are called columbite or niobite. Tantalum's name also reflects its close relationship with niobium - in Greek mythology Niobe was the daughter of Tantalus.

Various countries around the world, particularly Australia and Brazil, have significant tantalum deposits and mining operations. Tantalum is widely used in the electronics industry to produce capacitors and resistors and can also be alloyed with other elements to produce parts for jet engines and nuclear reactors (amongst other things). As it is inert and corrosion-resistant it is also useful for making medical implants such as replacement hips and knees.

Answer: Tellurium

Tellurium takes its name from the Latin word 'tellus', meaning 'earth'. However, although you might therefore expect it to be commonly found in the earth, it is actually one of the rarest elements in the Earth's crust (about as rare as platinum). By contrast though it is estimated to be much more common elsewhere in the solar system. Anyone going digging for tellurium is unlikely to have much success, but if they do happen to find some then they should watch out as it can be toxic in large quantities and has a nasty habit of making human breath smell like garlic.

Tellurium is a member of group 16 of the periodic table, the same group that contains oxygen, sulfur and selenium. It can be used in both natural and synthetic processes as a replacement for both sulfur and selenium - for example in the production of amino acids in fungi or in the vulcanisation process of rubber.

Answer: Tin

Tin is an element which has been known and used by humans for thousands of years. The Bronze Age, which started around 3000 BC, was characterised by the development of processes to alloy tin with copper to create a range of objects, including weapons, ornaments, helmets and plates. Tin was a prized commodity during this era and long-distance ("international") trade in tin thrived in both Europe and in Asia, even in those early times.

Alloying tin with other metals remains one of the key uses of the element over 5,000 years after the start of the Bronze Age. The difference is that some of the uses tend to be a bit more sophisticated; examples include the nuclear power industry, the development of high-performance batteries and superconducting magnets. However, one area where tin is not used as extensively as it once was is in tin cans for storing food or liquids - most are actually made of steel or aluminium.