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    could someone please check my answer for this question? There aren't any answers :/

    NaHCO3 + HCl --> NaCl + H2O + CO2

    3.53g sodium hydrogencarbonate was added to 30cm3 of 2mol/dm3 hydrochloric acid. The temperature fell by 10.3C. Work out which reagent was in excess and then calculate the energy change in kJ/mol.

    This is what I did:
    HCl: 0.03dm3 * 2mol/dm3 = 0.06 mol
    NaHCO3: 0.06 mol should react (equation) but with the calculation (moles = mass/Mr) 0.04202... moles are present
    So HCl is in excess

    Q=mc#T
    Q = 30 * 4.2 * 10.3 = 1297.8J = 1.2978kJ

    enthalpy change: 1.2978/0.04.. = +30.8kJ/mol

    *I got confused with which value for moles I was meant to use??*
    THANKS x
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    bump?
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    (Original post by surina16)
    bump?
    Its fine assuming you havent made any arithmetic errors (i assumed you typed in everything correctly)
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    (Original post by samb1234)
    Its fine assuming you havent made any arithmetic errors (i assumed you typed in everything correctly)
    great thank you i was just unsure if I was meant to use 0.06 or 0.042.. for moles at the end
 
 
 
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