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Homework Help: Physical properties

  1. Jun 29, 2006 #1
    does metals has the following?

    Qns. high melting point, insoluble in water, conduct electricity in solid and liquid.

    may i know what's the physical properties of covalent compound?

    do they have low melting point?

    does ionic compound has high melting point ?

    can somebody correct me? thanks lotsa. :smile:
  2. jcsd
  3. Jun 29, 2006 #2


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    What does "Qns." stand for?

    Metals have a very broad range of melting points. Some metals are liquid at or near room temperature, other metals have very high melting points. Then one could even consider metal alloys (mixrtures of two or more metals) and change the melting points even further.

    I cannot think of any example of a pure metal being soluble in water to any significant degree.
    I would say metals are insoluble in water.

    One property of metals is that they conduct electricity.

    Covalent bonds (by comparison to ionic bonds) have lower melting points. Take the example of Carbon Dioxide (Carbon double covalently bonded to two Oxygen atoms), which has a much lower melting point than Sodium Chloride (NaCl).
    Generally, ionic compounds have fairly high melting points where as covalently bonded molecules have lower melting points.
  4. Jun 29, 2006 #3
    All metals either are insoluble in water or react with water (ie Na).
  5. Jun 30, 2006 #4
    metal will react with water in some situation, that is corrosion. Its the ionic reaction between metal, water and air. but the reaction is so slow, may be years. Generally, metal can consider does not react with water.
  6. Jun 30, 2006 #5


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    The example of the chemical reaction Cesium gave of Sodium (Na) metal reaction with water does not involve air and occurs quite quickly and spontaneously.
    2Na + 2H2O --> 2NaOH + H2 + Heat
    H2 + O2 + Heat --> Explosion

    Placing an Alkali/Alkaline earth metal (for example, Sodium, or even Cesium) in water produces quite a vigorous reaction to occur.
  7. Jun 30, 2006 #6
    Most definitely! ---> http://video.google.com/videoplay?docid=-2134266654801392897&q=braniac [Broken] !!
    Last edited by a moderator: May 2, 2017
  8. Jun 30, 2006 #7


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    Quite entertaining to say the least.

    "But for some reason they wouldn’t let us have any of that [Francium]".
    --And the fact that it has a half life of only about 22 minutes and there is only about 20-30 grams of it on Earth at any one time has nothing to do with that right?
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