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    im getting so confused! in my book it says 'in an exothermic reaction, the energy released in bond formation is greater than the energy used in BREAKING OLD BONDS'

    from what i understand, in an exothermic reaction, reactants join together/'bond' (and lose energy); so i understand how these bonds are formed. what i can't grasp is what it means by saying 'bonds are broken'; the reactants are separate before they react aren't they, so how can they have bonds to be broken?

    same with endothermic; i'm confused about old/new bonds?

    hope my question makes sense! i'll try and reword if it doesn't
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    They do have bonds, take for example:

    NaOH + HCl --> NaCl + H2O

    The reactants have 1 Na-OH bond, and 1 H-Cl bond. To break those, it takes in energy from the surroundings.

    The products make new bonds; 1 Na-Cl bond and 2 H-O bonds. To make these, it releases energy to the surroundings.

    If the energy taken in is greater than energy released, it is endothermic, and if not, it is exothermic. HTH
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    (Original post by Excalibur)
    They do have bonds, take for example:

    NaOH + HCl --> NaCl + H2O

    The reactants have 1 Na-OH bond, and 1 H-Cl bond. To break those, it takes in energy from the surroundings.

    The products make new bonds; 1 Na-Cl bond and 2 H-O bonds. To make these, it releases energy to the surroundings.

    If the energy taken in is greater than energy released, it is endothermic, and if not, it is exothermic. HTH
    thanks a lot excalibur! i finally grasp the concept!
 
 
 

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