Chemistry ---Elements, Compounds and Mixtures

• baiyun

  2 May 10, 15:29

  Please help.Thank you.

  All substances that decompose are compounds. Is this statement true?

• UltimaOnline

  2 May 10, 16:28

  Originally posted by baiyun:

  Please help.Thank you.

  All substances that decompose are compounds. Is this statement true?

  
  By definition of "decompose", yes the statement is true.

   

  It's possible to transform a sample of an element from one allotrope to another, with appropriate application of heat and/or pressure, but we don't call it "decomposition".

   

  Note that the compound may be covalent/molecular, eg. H2O(l); or it may be ionic, eg. Mg(NO3)2(s).