Delta H Calculation: 7.455 + 94 + 8.4

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Discussion Overview

The discussion revolves around the calculation of ΔH (enthalpy change) using a specific formula. Participants are attempting to clarify the components of the formula and the values to be used, including mass and specific heat capacities.

Discussion Character

  • Technical explanation, Conceptual clarification, Debate/contested

Main Points Raised

  • One participant presents a formula for calculating ΔH: -(msolution x csolution + C) ΔT, with specific values for msolution, Csolution, and C.
  • Another participant questions the correctness of the mass used in the calculation, stating that the mass of the solution is 187.5 g.
  • A subsequent reply provides a breakdown of the mass, indicating it consists of 180 g of water and 7.5 g of KCl, totaling 187.5 g.
  • There is a request for clarification regarding the mass of the solution and the reasoning behind it.
  • One participant expresses confusion about the initial post and requests elaboration on the terms used, emphasizing the need for units in the calculations.

Areas of Agreement / Disagreement

Participants do not appear to reach consensus on the initial calculation or the values used, with multiple viewpoints on the mass of the solution and the formula's application remaining contested.

Contextual Notes

There are unresolved questions regarding the definitions of terms and the assumptions behind the values used in the calculation, particularly concerning the specific heat capacities and their relevance to the overall formula.

aname
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Homework Statement
i'm not sure I used the numbers right
Relevant Equations
Determination of the dissolution enthalpy
-(7.455 so,94+8,4) Delta T

C44A1456-0723-4621-817E-495206630632.png
C3D2CAEC-90E4-4594-8CE7-35516959ECB4.png
 
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No idea what is what of what, please elaborate.

And please don't omit units.
 
Hi Borek,

I need to calculate ΔH.
And I used this Formular -(msolution x csolution+C) ΔT

msolution= 7.455
Csolution=0,94
C=8,9

it this correct ?
 
No. m of the solution is 187.5 g.
 
Chestermiller said:
No. m of the solution is 187.5 g.
Hi,
Can you explain me why the solution is 187,5
 
There are 180 g of water and 7.5 g of KCl, totaling 187.5 g.
 

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