Pottery Salt

9 Dec, 2004 in art pottery by admin

Pottery Salt

Lithium and Mental Health

Lithium (Greek lithos, “stone”), the first of the alkali metals in the periodic table, is a silvery white, chemically reactive metallic element that is the lightest in weight of all metals and ranks 35th in order of abundance of the elements in Earth’s crust. It does not occur in nature in the free state but only in compounds, which are widely distributed. In nature it is found like a mixture of the isotopes Li-6 and Li-7. Many of its physical and chemical properties are more similar to those of the alkaline earth metals than to those of its own group elements. Among the most significant properties of lithium, we find its high specific heat (calorific capacity), the huge temperature interval in the liquid state, high thermic conductivity, low viscosity and very low density. Metallic lithium is soluble in short chain aliphatic amines but it is insoluble in hydrocarbons.

Johann A. Arfvedson is generally credited to have discovered the element in 1817D. Chemically, lithium resembles sodium in its behavior and it is obtained by the electrolysis of a mixture of fused lithium and potassium chloride. It tarnishes instantaneously and corrodes rapidly upon exposure to air; hence when it is stored it must be immersed in a liquid such as naphtha. The metal is used as a deoxidizer and to remove unwanted gases during the manufacture of nonferrous castings. Lithium melts at about 181°C, boils at about 1342°C, and has a specific gravity of 0.53.

Lithium takes part in a large number of reactions, both with organic as well as inorganic reactants. It reacts with oxygen to form its monoxide and peroxide. It is the only alkali metal that reacts with nitrogen at ambient temperature to produce black nitre. Metallic lithium’s reaction with water is extremely vigorous. Lithium reacts directly with the carbon to produce the carburet. It binds easily with halogens and forms halogenates with light emission. Although it doesn’t react with paraffinic hydrocarbons, it experiments addition reactions with alquenes substituted by aryl and diene groups.

The main lithium compound is the lithium hydroxide that is a white powder (the manufactured material is monohydrate lithium hydroxide.) The carbonate is generally used in the pottery industry and in medicine as an antidepressant. The bromine and the lithium chloride both form concentrated brine, which have the property of absorbing the humidity in a wide interval of temperature; these brines are used in the manufacture of air conditioning systems. The main industrial use of lithium is in lithium stearate form, as lubricant grease’s thickener. Other important applications of lithium compounds are in pottery, specifically in porcelain glaze; as an additive to extend the life and performance of alkaline storage batteries and in autogenous welding and brass welding.
Alloys of the metal with many metals are used to make high performance aircraft parts. Lithium vapor is used to prevent carbon dioxide and oxygen from forming scale in furnaces in heat-treating steel. Important compounds of lithium include the hydroxide, used for bonding carbon dioxide in the ventilator systems of spacecraft and submarines; and the hydride, used to inflate lifeboats, and its heavy hydrogen (deuterium) equivalent, used in making the hydrogen bomb. Lithium carbonate, a common mineral, is used in the treatment of some forms of manic depression.

Like all alkali metals, lithium reacts easily in water and does not occur freely in nature due to its activity, Lithium is a moderately abundant element and is present in the Earth’s crust in 65 ppm (parts per million). Today, most commercial lithium is recovered from brine sources in Chile. Lithium is easily adsorbed by plants. The amount of lithium in plants varies widely, in some cases reaching 30 ppm. Metallic lithium reacts with a number of elements and water vapor in air. Consequently, the lithium surface becomes coated with a mixture of lithium hydroxide (LiOH), lithium carbonate (Li2CO3), and lithium nitride (Li3N). Lithium hydroxide represents a potentially significant hazard because it is extremely corrosive. Special attention should be given to its contact with water organisms.

Many reactions may cause fire or explosion when exposed to Lithium. It gives off irritating or toxic fumes (or gases) in a fire. There is risk of fire and explosion on contact with combustible substances and water. On inhalation it gives burning sensation, coughs, labored breathing, shortness of breath, and sore throat. However, the symptoms may be delayed. When it comes in contact of the skin, the skin becomes red. On ingestion, there are chances of abdominal cramps, abdominal pain, burning sensation, nausea, shock or collapse, vomiting, and weakness. The substance is corrosive to the eyes, the skin and the respiratory tract. Inhalation of the substance may cause lung oedema. The symptoms of lung oedema are often not manifested until a few hours have passed and they are aggravated by physical effort.

Rest and medical observation is, therefore, essential in all cases of probable actions of lithium. Immediate administration of an appropriate spray, by a doctor or a person authorized by him/her, should be considered. The substance can be absorbed into the body by inhalation of its aerosol and by ingestion. Inhalation due to evaporation at 20°C is negligible; a harmful concentration of airborne particles can, however, be reached quickly when dispersed. Heating the element may cause violent combustion or explosion. The substance may spontaneously ignite on contact with air when finely dispersed. Upon heating, toxic fumes are formed. It reacts violently with strong oxidants, acids and many compounds causing fire and explosion hazards. It also reacts violently with water, forming highly flammable hydrogen gas and corrosive fumes of lithium hydroxide.

The saga of the use of lithium ion to treat a mental disorder is an example of how a discovery is made through a combination of accident (serendipity) and observation. In 1938 an Australian psychiatrist, J. Cade, Was studying the effects of a large organic anion on animals. To increase the dosage, he needed a more soluble salt. For large anions, the solubility of the alkali metal ions increase as their radii decrease; hence he chose a lithium salt. However, when he administered this compound, the animals started to showing behavioral changes which made him realized that the lithium ion itself must have had an effect on the workings of the brain. Further studies showed that the lithium ion had a profound effect on manic depressive patients.

To this day, lithium ion is the safest and most effective treatment for manic depression; although careful dosage and monitoring are crucial because too much lithium ion can cause cardiac arrest (a blood level of 1 x 10-3 mol.L-1 is optimal). However, its mechanism of action is still not well understood. It seems plausible to assume that it may work by affecting the sodium potassium or magnesium-calcium balance in the body. Ironically, the discovery of the health effects of lithium could have been made much earlier, because it tad been well known in folk medicine that water from certain lithium-rich British springs helped alleviate the manic disorder. More recently, a study in Texas showed that locations having lower levels of hospital admissions with manic depression have higher levels of lithium ion in the local drinking water.

About the Author

Dr.Badruddin Khan teaches Chemistry in the University of Kashmir, Srinagar, India. Besides striving to contribute towards the cause of society by enriching its roots of desired fruit and the most valuable raw materials, the students, he tries his level best to make his brethren informed citizens by his write-ups. His contact-details are: E.mail:khanbudr@yahoo.co.in; Phone:00919906415909.

Math problem?

An archaeologist uncovers a strange thing: a box that contains a set of six clay balls, baked just as if they were pottery. Also in the box are two wooden plates and remnants of string, which are obviously from an old balance. She weighs the balls and finds that two weigh 7/8 gram, and the other four weigh, respectively, ¾ gram more than 1 gram, 3 and a half grams, 7 grams, and 3 grams. Clearly, they are intended to weigh something, perhaps salt or spices.

What is the smallest amount this balance could weigh, and how?
Describe how you could use these weights to accurately weigh something a hundred times as heavy as the largest weight in the box?
Describe how you could use these weights to create a new set that would start at 1/8 gram?

Do your own homework. No one wants to do it for you.

Throwing Making a simple small flattened clay pottery salt holder pot on the wheel