Chemistry Essay Example | Topics and Well Written Essays - 1000 words

Chemistry - Essay Example In this conformation there is no steric strain and no torsional strain. Due to the migration of electrons towards the more electronegative nucleus in a bond between two different elements the molecules become polarized. In larger molecules a number of poles form and this causes some parts of the molecule to attract and some to repel each other. In the butane molecule both ends of the molecule are rotating around the C-C bond and take different configurations (these are constantly changing. Steric strain is caused by the crowding together of groups – as explained above the groups are forced to approach each other till they touch, but because of their similar polarity they are under forces of repulsion also. This leads to the molecule possessing extra potential energy, this energy is called steric strain. a. In 1870, Markonikov laid down a basic principle of chemistry that holds till today. The Markonikov Rule states that when a hydrogen halide (Hydrochloric acid, HCl being an example) reacts with an asymmetrically substituted alkene the hydrogen attaches itself to the carbon atom that has the larger number of its hydrogen atoms substituted. The halogen automatically attaches itself to the carbon atom having the least number of its hydrogens substituted. An example of such an addition reaction: b. Enantiomers are two molecules of the same chemical that are the mirror image of each other, like our hands, they are similar but yet not the same and can not be superimposed on each other. Such molecules are called Enantiomers. They are not isomers and are not different from each other in any way except in their configuration. c. An Emperical formula gives the proportion of the constituent elements in the molecule but does not give the exact composition of the molecule. The empirical formula represents the mole fraction/ ratio of each element in the compound. For example the empirical formula may show that there is hydrogen and