Delta H Calculation: 7.455 + 94 + 8.4

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SUMMARY

The discussion centers on the calculation of ΔH using the formula ΔH = (msolution x csolution + C) ΔT. The values provided include msolution = 7.455 g, Csolution = 0.94 J/g°C, and C = 8.9 J/g°C. The correct total mass of the solution is established as 187.5 g, derived from 180 g of water and 7.5 g of KCl. This clarification is crucial for accurate ΔH calculations.

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  • Basic knowledge of mass and its role in solution calculations.
  • Ability to perform unit conversions and arithmetic operations in scientific contexts.
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Chemistry students, laboratory technicians, and professionals involved in thermodynamic calculations and calorimetry. This discussion is particularly beneficial for those learning to calculate enthalpy changes in chemical solutions.

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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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