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Topic: HARD CALORIMETRY PROBLEM with unknown elements  (Read 4741 times)

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Offline CaO(lime)

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HARD CALORIMETRY PROBLEM with unknown elements
« on: April 14, 2008, 01:02:02 PM »
A coffee cup calorimeter was standardized using 40.0 mL of 1.00 M HCl and 80.00 mL  of 0.500 M M(OH)2. The neutralization reaction gave a temperature rise of 10.680C. The same calorimeter cup was used to determine the neutralization reaction of diprotic acid, H2A and M(OH)2 forming a precipitate, MA and water; 40.00 mL of 0.850 H2A and 80.00 mL of 0.500 M M(OH)2 was used for this setup giving a temperature rise of 11.60C.
Given: DELTA H0neutralization for calibration= -111.66kJ/mol

q1: Calculate the heat capacity of the calorimeter in kJ/K.

       I don't even know how to start. I know how to calculate the heat capacity of a calorimeter, given the energy spent or the specific heat of the water (normally, there's water involved right?). But here, I don't know how to manipulate any of these values. What does standardizing mean? I mean, when it comes to the calorimetry? And why are there two starting reactants for the calibration? Am I supposed to get the the limiting reactant? But once i do, what then?

q2: If the neutralization reaction of H2A and M(OH)2 released 143.84 kJ of heat per mole, calculate the mass of the precipitate produced in the reaction. Given: specific heat of MA = 0.008 kJ g-1 K-1.

        And what's a neutralization reaction? What does that entail? And can someone please tell me how I can calculate for the mass of the ppt given that the element that it's made of are phantom elements?



I'd be eternally grateful if you guys would help me with this.




« Last Edit: April 15, 2008, 09:33:14 AM by THONG_GURL »

Offline TaSt3MyRa1nBoW

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Re: HARD CALORIMETRY PROBLEM with unknown elements
« Reply #1 on: April 14, 2008, 02:08:53 PM »
are we related? i dont capitalize or punctuate my words either!?!?! watch out for a few on here, they get ANGRY when things are not punctuated correctly!  ::)
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