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Hydrogen bonds

  1. Jan 26, 2005 #1
    Hydrogen bonds!!!

    Hey, sorry to bother you guys with middle school stuff. I am a HS freshmen, and I got hydrogen bonds and the H20 covalent bond mixed up. What are the difference? Haha.
  2. jcsd
  3. Jan 26, 2005 #2


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    The H2O covalent bond is due to H atoms "sharing" their outer electrons with the O atom (which likes to attract electrons) within a molecule. This sharing creates a strong bond that is very hard to break (it takes about 430 kJ/mol to break either of the H-O-H bonds).

    Now this sharing is hardly an equal sharing. The shared electrons are closer to the O atom (because of its electronegative nature, it likes to attract electrons), making it have a partial negative charge. As a result, the H atom has a partial positive charge. This difference in charge makes the O-H bonds "polar", and hence water is known as a polar molecule. But what this does is that now the negatively charged O atom will tend to attract any loose positive cherges towards it. These are found on the H atoms of nearby water molecules. As a result, there exists a weak bonding between the molecules, which is known as Hydrogen Bonding (it takes around 10 to 40 kJ/mol to break hydrogen bonds).

    Note : Important differences are underlined.
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