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A solid crystalline substance, cubane is one of the Platonic hydrocarbons and a member of the prismanes. It was first synthesized in 1964 by Philip Eaton and Thomas Cole. [4] Before this work, Eaton believed that cubane would be impossible to synthesize due to the "required 90 degree bond angles".
A comparison between the five platonic solids and the corresponding three platonic hydrocarbons. In organic chemistry, a Platonic hydrocarbon is a hydrocarbon whose structure matches one of the five Platonic solids, with carbon atoms replacing its vertices, carbon–carbon bonds replacing its edges, and hydrogen atoms as needed. [1] [page needed]
Solid: A solid holds a definite shape and volume without the need of a container. The particles are held very close to each other. Amorphous solid: A solid in which there is no far-range order of the positions of the atoms. Crystalline solid: A solid in which atoms, molecules, or ions are packed in regular order.
In a solid, constituent particles (ions, atoms, or molecules) are closely packed together. The forces between particles are so strong that the particles cannot move freely but can only vibrate. As a result, a solid has a stable, definite shape, and a definite volume. Solids can only change their shape by an outside force, as when broken or cut.
The angle between the C-C bonds in each carbon atom is 108°, which is the angle between adjacent sides of a regular pentagon.That value is quite close to the 109.5° central angle of a regular tetrahedron—the ideal angle between the bonds on an atom that has sp 3 hybridisation.
the number of molecules, etc. in a given amount of material is a fixed dimensionless quantity that can be expressed simply as a number, not requiring a distinct base unit; [5] [24] The SI thermodynamic mole is irrelevant to analytical chemistry and could cause avoidable costs to advanced economies [ 25 ]
A molecular solid is a solid consisting of discrete molecules. The cohesive forces that bind the molecules together are van der Waals forces, dipole–dipole interactions, quadrupole interactions, π–π interactions, hydrogen bonding, halogen bonding, London dispersion forces, and in some molecular solids, coulombic interactions.
The symmetry groups of the Platonic solids are a special class of three-dimensional point groups known as polyhedral groups. The high degree of symmetry of the Platonic solids can be interpreted in a number of ways. Most importantly, the vertices of each solid are all equivalent under the action of the symmetry group, as are the edges and faces.