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Homework Help: Arranging Chemical reactions into

  1. Aug 12, 2006 #1
    Metal AX BX CX DX EX
    A - + + + +
    B + - + - -
    C + + - + -
    D - - - - -
    E + + + + -

    Arrange the following metals A,B,C,D and E according to increasing reactivity out of the information
    given above. Use The Symbol of greater than (>) in indicating that one metal is more reactive than the other. Ex A>B>E means metal A is more reactive than B and B is more reactive than E.

    Dont know were to start...
    i just know that E + AX = There is a reaction where E > A etc.
  2. jcsd
  3. Aug 13, 2006 #2


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    What information is this? What do the entries (+,-) in this matrix represent?
  4. Aug 13, 2006 #3
    + means that there is a reaction
    - means that there's no reaction

    and my diagram is a table... and sorry for that, cant skip it
  5. Aug 13, 2006 #4
    If a metal A displace out another metal B from another metal's solution (BX), then this means that metal A is more reactive than metal B.

    From the first row of the table, we can get A>B, A>C, A>D, A>E.
    Then, from the second row, we get, B>A and B>C.
    For the third row, C>A, C>B and C>D,
    From the 4th row, we can conclude that metal D is the least reactive among the 5 metals.
    5th row, E>A, E>B, E>C, E>D.

    However, I think there is something wrong with this question, since we get A>B, and B>A, (and many other contradictions) which only one of them can be true.

    Can you please check back the question? Thanks.:smile:
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