Each of these sp 3 -hybridized atoms is then bound to four other carbon atoms, which form bonds to four other carbon atoms, and so on. As a result, a perfect diamond can be thought of as a single giant molecule. The strength of the individual C-C bonds and their arrangement in space give rise to the unusual properties of diamond.
In some ways, the properties of graphite are like those of diamond. Both compounds boil at o C, for example. But graphite is also very different from diamond. Diamond 3. Whereas diamond is the hardest substance known, graphite is one of the softest. Diamond is an excellent insulator, with little or no tendency to carry an electric current. Graphite is such a good conductor of electricity that graphite electrodes are used in electrical cells.
The physical properties of graphite can be understood from the structure of the solid shown in the figure below. Graphite consists of extended planes of sp 2 -hybridized carbon atoms in which each carbon is tightly bound to three other carbon atoms.
The strong bonds between carbon atoms within each plane explain the exceptionally high melting point and boiling point of graphite. The distance between these planes of atoms, however, is very much larger than the distance between the atoms within the planes. Because the bonds between planes are weak, it is easy to deform the solid by allowing one plane of atoms to move relative to another.
As a result, graphite is soft enough to be used in pencils and as a lubricant in motor oil. This is fortunate because many people chew pencils and lead compounds are toxic.
Increasing the percentage of clay makes the pencil harder, so that less graphite is deposited on the paper. The characteristic properties of graphite and diamond might lead you to expect that diamond would be more stable than graphite.
This is not what is observed experimentally. At very high temperatures and pressures, diamond becomes more stable than graphite. In General Electric developed a process to make industrial-grade diamonds by treating graphite with a metal catalyst at temperatures of to K and pressures above , atm. Although gem-quality diamonds can be synthesized, the costs involved are prohibitive.
Both diamond and graphite occur as regularly packed crystals. Other forms of carbon are amorphous they lack a regular structure. Charcoal, carbon black, and coke are all amorphous forms of carbon. Charcoal results from heating wood in the absence of oxygen. To make carbon black , natural gas or other carbon compounds are burned in a limited amount of air to give a thick, black smoke that contains extremely small particles of carbon, which can be collected when the gas is cooled and passed through an electrostatic precipitator.
Coke is a more regularly structured material, closer in structure to graphite than either charcoal or carbon black, which is made from coal.
Carbides: Covalent, Ionic, and Interstitial. Although carbon is essentially inert at room temperature, it reacts with less electronegative negative elements at high temperatures to form compounds known as carbides. When carbon reacts with an element of similar size and electronegativity, a covalent carbide is produced. Silicon carbide, for example, is made by treating silicon dioxide from quartz with an excess of carbon in an electric furnace at K.
This is an extremely important area to industry, and many of the chemists who would be identified as inorganic or organometallic chemists work in this area. Materials Chemistry is an area concerned with the design and synthesis of materials that allow the advance of technologies in nearly every area of society. Often, inorganic chemists working in this area are concerned with the synthesis and characterization of solid state compounds or inorganic polymers such as silicones.
Bioinorganic chemists study the function of metal-containing compounds within living organisms. Students who concentrate in inorganic chemistry often go on to work in industry in polymer or materials science, do research or teach in inorganic chemistry, or pursue other related job opportunities. Biochemistry Biochemistry is the study of the chemical principles underlying basic biological systems.
Fundamentally, biochemical research aims to characterize the link between the structure and function of biological macromolecules. Students who concentrate in biochemistry go on to pursue extremely successful careers in medicine, research, and business. Some students may go on to professional schools directly after completing their undergraduate degrees, while others may enter academic or governmental research settings.
The combined study in biochemistry and business provides these students with the unique ability to better weigh the cost to profit margin during biochemical product generation. For information on the Biochemistry major, click here. Graphics Legend: Organic chemistry : Reduction of camphor by sodium borohydride.
Analytical chemistry : Mass spectrum of diethylamine. Carbon compounds all around This topic explores ways to introduce students to organic chemistry — the chemistry Hydrocarbons and fuels This topic looks at the hydrocarbons, the most fundamental class of organic Why carbon is special This topic looks at the special nature of carbon — the key factors that allow carbon Representing organic structures The size and complexity of organic molecules results in a need to describe these Frameworks and functional groups 1 The study of the reactions of organic compounds is really a study of functional Frameworks and functional groups 2 In the previous topic we introduced the concept of the functional group and Isomerism Part of the complexity of carbon chemistry arises from the fact that most carbon Patterns in physical properties Although organic compounds are usually studied by a consideration of their chemical Organic reactions — key principles Although organic reactions are often complex, we can apply basic principles and Helmenstine, Anne Marie, Ph.
The 5 Main Branches of Chemistry. Overview of the Branches of Chemistry. List of the Strong Acids and Key Facts. Pure Substance Definition in Chemistry. Topics Typically Covered in Grade 11 Chemistry. Your Privacy Rights. To change or withdraw your consent choices for ThoughtCo. At any time, you can update your settings through the "EU Privacy" link at the bottom of any page. These choices will be signaled globally to our partners and will not affect browsing data.
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