Wednesday, June 13, 2012

Pure and impure substances



  


A pure substance is one which is made up of only one kind of molecules.It has definite composition and properties.All elements and compounds are pure substances.Some examples are oxygen,hydrogen,gold,silver,copper,common,salt,pure water ,alum.An impure substance is one which is a mixture of two or more kinds of molecules and has no definite composition and properties.for example air,soil,atones and pebbles in food grains,sugar in water,sand in water,fruit juice etc.

13 comments:

  1. ya but u didnt define it properly...

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  2. what about concrete,oxygen gas,paper, and cigarette smoke?

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    Replies
    1. oxygen is a pure substance.because it is a non metal element
      gas is a impure substance because it is a mixture of various constituents.
      paper is pure substance.because it is a non metal element.
      cigarette smoke is a impure substance.because cigarette itself a impure substance as it is made up of lot of toxics substances...

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  3. I can define a substance as "A part of matter which is under scientific obersation". It can be classified as pure (elements and compounds) and impure (mixtures).

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  4. I think it was really good and you did a very good job of explaining it.

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  5. can someone explain with respect to boiling and melting points

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  6. Boiling point is accurate when it's a pure substance but when it's impure, it's results inaccurately in boiling and melting point, but most of the time the so called pure substance such as pure water has some constituents:

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  7. This is a meaning my teacher gave me...
    Pure substances contains only one type of materials.an element such as gold is a pure substances because it is made up of atoms of which is identical.

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  8. This is a meaning my teacher gave me...
    Pure substances contains only one type of materials.an element such as gold is a pure substances because it is made up of atoms of which is identical.

    ReplyDelete
  9. This is a meaning my teacher gave me...
    Pure substances contains only one type of materials.an element such as gold is a pure substances because it is made up of atoms of which is identical.

    ReplyDelete
  10. oxygen is a pure substance.because it is a non metal element
    gas is a impure substance because it is a mixture of various constituents.
    paper is pure substance.because it is a non metal element.
    cigarette smoke is a impure substance.because cigarette itself a impure substance as it is made up of lot of toxics substances...

    ReplyDelete