6: Anthracite (12 Days of Christmas with chemistry)

Anthracite is a hard, compact variety of coal that has a submetallic luster. It has the highest carbon content, the fewest impurities, and the highest calorific content of all types of coal except for graphite.

Anthracite is the most metamorphosed type of coal (but still represents low-grade metamorphism), in which the carbon content is between 92.1% and 98%.^[1][2] The term is applied to those varieties of coal which do not give off tarry or other hydrocarbon vapours when heated below their point of ignition. Anthracite ignites with difficulty and burns with a short, blue, and smokeless flame.

Anthracite is categorized into standard grade, which is used mainly in power generation, and high grade (HG) and ultra high grade (UHG), the principal uses of which are in the metallurgy sector. Anthracite accounts for about 1% of global coal reserves,^[3] and is mined in only a few countries around the world. China accounts for the majority of global production; other producers are Russia, Ukraine, North Korea, South Africa, Vietnam, the UK, Australia and the US. Total production in 2010 was 670 million tons.^[4]

5: Glowing Plectrum (12 Days of Christmas with chemistry)

A plectrum is a small flat tool used to pluck or strum a stringed instrument. For hand-held instruments such as guitars and mandolins, the plectrum is often called a pick, and is a separate tool held in the player's hand. In harpsichords, the plectra are attached to the jack mechanism.

A plectrum (pick) for electric guitars, acoustic guitars, bass guitars and mandolins is typically a thin piece of plastic or other material shaped like a pointed teardrop or triangle. The size, shape and width may vary considerably. Thin items such as small coins, bread clips or broken compact discs and credit cards can be used as substitute plectra. Banjo and guitar players may wear a metal or plastic thumb pick mounted on a ring, and bluegrass banjo players often wear metal or plastic fingerpicks on their fingertips. Guitarists also use fingerpicks.

Guitar picks are made of a variety of materials, including celluloid, metal, and rarely other exotic materials such as turtle shell, but today delrin is the most common^{[citation needed]}. For other instruments in the modern day most players use plastic plectra but a variety of other materials, including wood and felt (for use with the ukulele) are common. Guitarists in the rock, blues, jazz and bluegrass genres tend to use a plectrum, partly because the use of steel strings tends to wear out the fingernails quickly, and also because a plectrum provides a more 'focused' and 'aggressive' sound. Many guitarists also use the pick and the remaining right-hand fingers simultaneously to combine some advantages of flat picking and finger picking. This technique is called hybrid picking.

4: Drink Receptacles (12 Days of Christmas with chemistry)

3: Element Pins (12 Days of Christmas with chemistry)

A chemical element or element is a species of atoms having the same number of protons in their atomic nuclei (i.e. the same atomic number, Z).^[1]There are 118 elements that have been identified, of which the first 94 occur naturally on Earth with the remaining 24 being synthetic elements. There are 80 elements that have at least one stable isotope and 38 that have exclusively radioactive isotopes, which decay over time into other elements. Ironis the most abundant element (by mass) making up the Earth, while oxygen is the most common element in the crust of the earth.^[2]

Chemical elements constitute all of the ordinary matter of the universe. However astronomical observations suggest that ordinary observable matter is only approximately 15% of the matter in the universe: the remainder is dark matter, the composition of which is unknown, but it is not composed of chemical elements.^[3] The two lightest elements, hydrogen and helium were mostly formed in the Big Bang and are the most common elements in the universe. The next three elements (lithium, beryllium and boron) were formed mostly by cosmic ray spallation, and are thus more rare than those that follow. Formation of elements with from six to twenty six protons occurred and continues to occur in main sequence stars via stellar nucleosynthesis. The high abundance of oxygen, silicon, and iron on Earth reflects their common production in such stars. Elements with greater than twenty-six protons are formed by supernova nucleosynthesis in supernovae, which, when they explode, blast these elements far into space as planetary nebulae, where they may become incorporated into planets when they are formed.^[4]

2: Periodic Table Blankets (12 Days of Christmas with chemistry)

The modern periodic table is sometimes expanded into its long or 32-column form by reinstating the footnoted f-block elements into their natural position between the s- and d-blocks. Unlike the 18-column form this arrangement results in "no interruptions to the sequence [of] increasing atomic numbers".^[92] The relationship of the f-block to the other blocks of the periodic table also becomes easier to see.^[93] Jensen advocates a form of table with 32 columns on the grounds that the lanthanides and actinides are otherwise relegated in the minds of students as dull, unimportant elements that can be quarantined and ignored.^[94]Despite these advantages the 32-column form is generally avoided by editors on account of its undue rectangular ratio (compared to a book page ratio)

1: Tartaric Acid (12 Days of Christmas with chemistry)

Tartaric acid was first isolated from potassium bitartrate circa 800 AD, by the alchemist Jābir ibn Hayyān.^[4] The modern process was developed in 1769 by the Swedishchemist Carl Wilhelm Scheele.

Tartaric acid played an important role in the discovery of chemical chirality. This property of tartaric acid was first observed in 1832 by Jean Baptiste Biot, who observed its ability to rotate polarized light. Louis Pasteur continued this research in 1847 by investigating the shapes of ammonium sodium tartrate crystals, which he found to be chiral. By manually sorting the differently shaped crystals under magnification, Pasteur was the first to produce a pure sample of levotartaric acid.