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CAN YOU NOW DEPICT A MOLECULE OF WATER SHOWING THE NATURE OF BONDING BETWEEN ONE OXYGEN ATOM AND TWO HYDROGEN ATOMS?DOES THE MOLECULE HAVE SINGLE BONDS OR DOUBLE BONDS?WHAT WOULD HAPPEN IN THE CASE OF A DIATOMIC MOLECULE OF NITROGEN?

In water, each hydrogen nucleus is covalently bound to the central oxygen atom by a pair of electrons that are shared between them. In H2O, only two of the six outer-shell electrons of oxygen are used for this purpose, leaving four electrons which are organized into two non-bonding pairs. The four electron pairs surrounding the oxygen tend to arrange themselves as far from each other as possible in order to minimize repulsions between these clouds of negative charge. This would ordinary result in a tetrahedral geometry in which the angle between electron pairs (and therefore the H-O-H bond angle) is 109.5°. However, because the two non-bonding pairs remain closer to the oxygen atom, these exert a stronger repulsion against the two covalent bonding pairs, effectively pushing the two hydrogen atoms closer together. The result is a distorted tetrahedral arrangement in which the H—O—H angle is 104.5°. But when the H2O molecules are crowded together in the liquid, these attractive forces exert a very noticeable effect, which we call hydrogen bonding. And at temperatures low enough to turn off the disruptive effects of thermal motions. Water has two O-H single bonds. Nitrogen molecule have one or more unshared electron pairs,and has a negative partial charge. The hydrogen, which has a partial positive charge tries to find another atom of nitrogen with excess electrons to share and is attracted to the partial negative charge. This forms the basis for the hydrogen bond. 



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