Do polymers have high or low melting points? Polymers consist of very long molecules that contain chains of carbon. They too are held together by very strong covalent bonds. There are greater intermolecular forces between the long chains compared with smaller simple molecules. This means that polym...
Molecules of saturated fats pack more closely than unsaturated fats. a) Assuming the same number of carbons which compound would have a higher melting point a saturated fat or unsaturated one? b) Why does the ability to pack closer affect the melting po ...
Explain why the melting point and boiling point of alkali metals are low. Briefly compare and contrast the properties of oxygen with those of hydrogen. Why does carbon make up all organic molecules? Why not silicon, which is also in the 4th group of the periodic table?
28. However, the additional presence of the aldehyde moiety on DOPAL has a diverse and higher reactivity that leads to a covalent and irreversible modification of multiple lysines on
palladium hydride;pincer ligand;hydrogen bonding;non-covalent interactions;reaction mechanism;proton transfer;formic acid dehydrogenation 1. Introduction Homogeneous catalysis allows the implementation of many practically important and fundamentally interesting processes under relatively mild conditions. Many systems ...
Superficially it might seem that the process is entropically disfavored as aggregates should have lower entropy than free monomers/oligomers; however, this decrease is compensated more than enough by the entropy increase due to water molecules being extruded from aggregating regions of the interacting...
(Covalent Compounds)-simplestformulaunitare molecules.Havelowmelting&boilingpts. •Molecularformula-showsthetypesand numbersofatomscombinedinasingle molecule. •BondLength-istheaverage distancebetween2bondedatoms. •BondEnergy-istheenergyrequired tobreakabond. •Itgivesusinformationaboutthe strengthofa...
non-covalent intermolecular interactions is most convenient way to create nanosized particles [1,2,12–31]. The formation of super- molecules and supramolecular assemblies by self-assembly makes it possible to control shape, “dentate” of colloidal particles and their ability to interact with substr...
Why do molecular substances have relatively low melting points? Why do chemists classify reactions? Why are reactions between ions in an aqueous solution generally much faster than reactions between covalent molecules? Why do covalent compounds not conduct electricity? Why is energy releas...
alongchainandnocovalentchemicalbonds existbetweenthechains,themacromolecules arecalledlinearpolymers. Mostofthepolymerswe‘lltalkaboutherearelinear polymers.Alinearpolymerismadeupofone moleculeafteranother,hooked(钩)togetherinalong chain.Thischainiscalledthebackbone(骨架). ...