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2009 DAT #66 physical change

Discussion in 'DAT Discussions' started by VDR, Aug 3, 2011.

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  1. VDR

    VDR
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    I am a bit confused on why this is the correct answer.

    Q: each of the following is an example of a chemical change except one. which one is the exception?

    a. hydrogen peroxide decomposing to form molecular oxygen and water.
    b. methanol burning in air with a colorless flame.
    c. aluminum foil melting at 660 C
    d. hydrochloric acid neutralizing a solution of sodium hydroxide
    e. iron metal rusting

    the correct answer is C. (aluminum foil melting at 660).

    Thanks
     
    #1 VDR, Aug 3, 2011
  2. FROGGBUSTER

    FROGGBUSTER
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    If something like ice melts, do you know why that's a physical change and not a chemical one? A physical change means nothing happens to the molecules themselves. You're not breaking covalent bonds. In the case of melting, all that's happening is that solid --> liquid, which is just furthering the intermolecular forces.
     
    #2 FROGGBUSTER, Aug 3, 2011
  3. OP
    OP
    VDR

    VDR
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    Thanks. Makes sense. I didn't focus on chemical vs. physical.
     
    #3 VDR, Aug 3, 2011
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