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    An excess of copper powder was added to 50.0cm of 0.60 mol dm AgNO3. The temperature increased from 24 to 32. Find the enthaply change for the reaction.

    I did 100x 4.18x 8= 3344

    is that right or not? Please help. I am so stuck.
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    I've moved this to the appropriate forum where you should get more responses.
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    (Original post by thapki123)
    An excess of copper powder was added to 50.0cm of 0.60 mol dm AgNO3. The temperature increased from 24 to 32. Find the enthaply change for the reaction.

    I did 100x 4.18x 8= 3344

    is that right or not? Please help. I am so stuck.
    silver ions are the limiting reagent and there are 0.6 * 0.05 mol of them = 0.03 mol

    ΔE = -mcΔT = -0.05 x 4.18 x 8 = -1.672 kJ

    Hence energy per mol of silver ions = -1.672/0.03 = -55.7 kJ

    But if you wish to have the energy change for the stoichiometric reaction as written then this shows 2 mol of silver ions:

    2Ag+ + Cu --> 2Ag + Cu2+

    So, you would need to multiply the answer by 2 = -111.5 kJ
 
 
 
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