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  QUESTION 6:                The boiling point of ammonia is higher than of phosphine. Explain   SOLUTION:                      Ammonia, NH3 have strong hydrogen bonding whereas phosphine, PH 3 have simple vander waals forces as intermolecular forces. Thus more energy is required to overcome hydrogen bonding present in ammonia. As a result ammonia has high boiling point than phosphine.   QUESTION 7:                An element X conducts electricity and melts at 660 0 C. It reacts vigorously with chlorine, after initial warning, to give a solid chloride of x. The solid chloride sublimes at 180 0 C. The chloride vapour has a relative molecular mass of 267 but at much higher temperatures it is known to disdociate to a single compound of relative molecular mass 133.5. When an aqueous solution of the chloride ...

  ----------- OF THE HYDROGENBONDING TO THE PHYSICAL PROPERTIES OF SUBSTANCES, INCULDING ICE AND WATER.               The electronegative elements like fluorine, oxygen and nitrogen are responsible for hydrogen bonding. Physical properties of such molecules are different from other molecules.   (1)        In liquid state water molecules are linked with one another through hydrogen bonding. This is why boiling point of hydrogen is more than covalent hydrides of same group. (2)        The water molecules in ice become more regular in structure through hydrogen bonding. The structure of ice is diamond like i.e; each oxygen atom of water molecule have four tetrahedral corners. Two corners are occupied by bonded pair and two by lone-pair of electrons, through lone pairs oxygen atom form two hydrogen bonds with the neighboring water molecules. Due to wide...