Swatch Internet Time is a way to measure time invented in 1998 by the Swatch manufacturing firm in Biel/Bienne, Switzerland. Time is shown as an "@" mark with three numerals. The day starts with @000 for midnight. Noon is @500. Just before midnight is @999. The thousand parts which make up a day are called "dot beats" (.beats). Each dot beat is one minute and 26.4 seconds long. Midnight is the same as Central European Winter Time (UTC+1)and Internet Time is the same all over the world. It does not change during the Summer. People can use it to plan phone calls or Internet meetings. Most types of Linux can show Internet Time as the desktop clock.
Test tube
A test tube is a kind of laboratory glassware, composed of a fingerlike length of glass tubing, open at the top, usually with a rounded lip at the top, and a rounded 'U' shaped bottom.
They range in size from a couple inches to several inches long, from a few millimeters to a couple centimeters in diameter. They are designed to allow easy heating of samples, to be held in a flame, and often are made of expansion-resistant glasses, such as borosilicate glass (known by brand-names such as Pyrex and Kimax).
Tests tubes are often preferred above beakers when multiple small chemical or biological samples have to be handled and/or stored.
Vacutainers are a type of test tube that can be used for both collection and storage of blood.
Beaker
A beaker is a kind of laboratory glassware. A beaker is a cylinder with a lip and a spout (a bend in the rim of the beaker which makes it easier to pour liquids without spilling any). A beaker is usually about the same width as its height. This makes beakers very stable and easy to handle. They may be made of plastic, glass, or borosilicate glass. Some beakers have marks on them to show about how much volume of liquid they hold - these can not be used for exact measurements.
Beakers are often used to make solutions and they are probably the most used piece of laboratory glassware.
Crucible
In chemistry, a crucible is a kind of laboratory equipment that is usually a small cup, about the size of a shot glass, made of porcelain or non-reactive metal. Crucibles are used to heat chemical compounds to very high temperatures using a gas burner. One of the earliest uses of platinum was as a material in crucibles. Metals such as nickel and zirconium are also used as a modern crucible material.
Lithium
Lithium (from Greek "lithos" 'stone') is a soft, silver-white metal with symbol Li. It is the third chemical element in the periodic table. This means that it has 3 protons in its nucleus and 3 electrons around it. Its atomic number is 3. Its mass number is 6.94. It has two common isotopes, Li and Li. Li is more common. 92.5% of lithium is Li. Lithium is a soft silvery metal that is very reactive. It is used in lithium batteries and certain medicines.
Lithium is one of the alkali metals. Lithium is a silvery solid metal (when freshly cut). It is very soft. Thus it can be cut easily with a knife. It melts at a low temperature. It is very light, similar to wood. It is the least dense metal and the least dense element in a solid or liquid state. It can hold more heat than any other solid element. It conducts heat and electricity easily.
It will react with water, giving off hydrogen to form a basic solution (lithium hydroxide). Because of this, lithium must be stored in petroleum jelly. Sodium and potassium can be stored in oil but lithium cannot because it is so light. It will just float on the oil and not be protected by it.
Lithium also reacts with halogens. It can react with nitrogen gas to make lithium nitride. It reacts with air to make a black tarnish and then a white powder of lithium hydroxide and lithium carbonate.
Lithium forms chemical compounds with only one oxidation state: +1. Most of them are white and unreactive. They make a bright red color when heated in a flame. They are a little toxic. Most of them dissolve in water. Lithium carbonate is less soluble in water than the other alkali metal carbonates like sodium carbonate.
It does not occur as an element in nature. It only is in the form of lithium compounds. The ocean has a large amount of lithium in it. Certain granites have large amounts of lithium. Most living things have lithium in them. There are some places where much lithium is in the salt. Some silicates have lithium in them.
Lithium (Greek "lithos", meaning "stone") was discovered by Johann Arfvedson in 1817. In 1818, Christian Gmelin observed that lithium salts give a bright red color in flame. W.T. Brande and Sir Humphrey Davy later used electrolysis on lithium oxide to isolate the element. Lithium was first used in greases. Then nuclear weapons became a big use of lithium. Lithium was also used to make glass melt easier and make aluminium oxide melt easier in making aluminium. Now lithium is used mainly in batteries.
It was apparently given the name "lithium" because it was discovered from a mineral, while other common alkali metals were first discovered in plant tissue.
It is made by getting lithium chloride from pools and springs. The lithium chloride is melted and electrolyzed. This makes liquid lithium and chlorine.
Its main use is in batteries. Lithium is used as an anode in the lithium battery. It has more power than batteries with zinc, like alkaline cells. Lithium ion batteries also have lithium in them, though not as an element. It is also used in heat transfer alloys. Lithium is used to make organolithium compounds. They are used for very strong bases.
It is used to make special glasses and ceramics, including the Mount Palomar telescope's 200 inch mirror. Lithium is the lightest known metal and can be alloyed with aluminium, copper, manganese, and cadmium to make strong, lightweight metals for aircraft.
Lithium compounds are used in some drugs known as mood stabilizers. Lithium niobate is used in radio transmitters in cell phones. Some lithium compounds are also used in ceramics. Lithium chloride can absorb water from other things. Some lithium compounds are used to make soap and grease. Lithium carbonate is used as a drug to treat manic depression disorder. Lithium carbonate is used for the treatment of bipolar disease and other mental illness conditions.
Organolithium compounds are used to make polymers and fine chemicals. Many lithium compounds are used as reagents to make organic compounds. Some lithium compounds like lithium aluminium hydride, lithium triethylborohydride, n-butyllithium and tert-butyllithium are commonly used as very strong bases called superbases.
Lithium compounds are used as pyrotechnic colorants and oxidizers in red fireworks and flares. Lithium chloride and lithium bromide are used as desiccants for gas streams. Lithium hydroxide and lithium peroxide are used to remove carbon dioxide and purify the air in spacecrafts and submarines. Lithium hydroxide, lithium peroxide and lithium perchlorate are used in oxygen candles that supply submarines with oxygen.
Lithium aluminum hydride can also be used as a solid fuel by itself. Lithium hydride that contains lithium-6 is used in thermonuclear weapons.
Lithium reacts with water, making irritating smoke and heat. It is not as dangerous as the other alkali metals. Lithium hydroxide is very corrosive.
There are 5 isotopes of Lithium having respectively 2, 3, 4, 5 and 6 neutrons in the nucleus. The most common isotope in nature is Li which makes up 92.58 % of the total. The second isotope which is widely available is Li which makes up 7.42 % of the total. The other 3 isotopes exist in very small quantities. The atomic mass of Lithium is 6.939.
Beryllium
Beryllium is in group 2 of the periodic table, so it is an alkaline earth metal. It is grayish (slightly gray) in color. It has an atomic number of 4 and is symbolized by the letters Be. It is toxic and should not be handled without proper training.
Beryllium has 4 electrons, 4 protons, and 5 neutrons.