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Anthracene is a solid polycyclic aromatic hydrocarbon (PAH) of formula C 14 H 10, consisting of three fused benzene rings. It is a component of coal tar . Anthracene is used in the production of the red dye alizarin and other dyes, as a Scintillator to detect high energy particles, as production of pharmaceutical drugs.
When comparing a polar and nonpolar molecule with similar molar masses, the polar molecule in general has a higher boiling point, because the dipole–dipole interaction between polar molecules results in stronger intermolecular attractions. One common form of polar interaction is the hydrogen bond, which is also known as the H-bond.
Most PAHs, like naphthalene, anthracene, and coronene, are planar. This geometry is a consequence of the fact that the σ-bonds that result from the merger of sp 2 hybrid orbitals of adjacent carbons lie on the same plane as the carbon atom. Those compounds are achiral, since the plane of the molecule is a symmetry plane.
Molecule must be cyclic. Every atom in the ring must have an occupied p orbital, which overlaps with p orbitals on either side (completely conjugated). Molecule must be planar. It must contain an odd number of pairs of pi electrons; must satisfy Hückel's rule: (4n+2) pi electrons, where n is an integer starting at zero.
9,10-Dibromoanthracene is an organic chemical compound containing anthracene with two bromine atoms substituted on its central ring. It is notable in that it was the first single molecule to have a chemical reaction observed by an atomic force microscope and scanning tunneling microscopy .
A naphthalene molecule can be viewed as the fusion of a pair of benzene rings. (In organic chemistry, rings are fused if they share two or more atoms.) As such, naphthalene is classified as a benzenoid polycyclic aromatic hydrocarbon (PAH). [19] The eight carbon atoms that are not shared by the two rings carry one hydrogen atom each.
In chemistry, hydrophobicity is the chemical property of a molecule (called a hydrophobe) that is seemingly repelled from a mass of water. [1] In contrast, hydrophiles are attracted to water. Hydrophobic molecules tend to be nonpolar and, thus, prefer other neutral molecules and nonpolar solvents.
The subsequent discovery (made by Broenner and Gutzhow in 1871) that anthracene could be abstracted from coal tar further advanced the importance and affordability of alizarin's artificial synthesis. [14] The synthetic alizarin could be produced for a fraction of the cost of the natural product, and the market for madder collapsed virtually ...