Help with Heat of Neutralization Homework

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The discussion centers on a homework problem regarding the heat of neutralization from a lab experiment involving HCl and NaOH. The participant calculated the heat absorbed by water as 1465.1 J and attempted to determine the enthalpy change (delta H) for the reaction. Confusion arises when calculating delta H per mole of water formed, as the participant mistakenly assumes 50 g of water produced 2.78 moles. The correct approach requires knowing the concentrations of the acid and base to accurately determine the moles of water formed in the reaction. The key takeaway is that delta H should be calculated based on the moles of water produced from the neutralization, not the initial volume of the solutions.
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Homework Statement


Im confused about this and need help
We did heat of nuetralization lab where we reacted 25mL of HCL and 25mL of NaOH using calorimeter.
The temp difference was an increase of exactly 7degC
One question asks me to show q_water (J) and to assume 50g water for the calculation
so i plugged in 50g * 4.186J/gdegC * 7degC = 1465.1J

Next it asks me what delta H_nuetralization (J) is and I wrote:
delta H_neut = q_rxn = -q_water = -1465.1J

Next it asks me for net ionic. I wrote
H^(aq) + + OH^-(aq) --> H2O(l)

Then it asks me for delta H_neut (kJ/mol), per mole of water formed and this is where I am confused, because internet search shows value should be about -58kJ/mol

50g water = 2.78mol
so if 50g water produces -1465.1J, then 1 mol water would produce 1465.1J / 2.775mol =527.0J
= 0.527kJmol - this is way off so I must be doing something wrong somewhere.
thanks for any help

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You didn't produce 50 g of water.

Were you given concentrations of NaOH and HCl?
 
Yes the whole experiement was nuetralization reaction. I had 25.0mL of NaOH and 25.0mL of HCl. I understand that the acid and base nuetralize each other and this is exothermic so heat given off but I am still confused about the whole concept for the enthalpy. thanks for any more help
 
ΔH = -58 kJ/mol means that 58 kJ of heat are released when 1 mole of H+ reacts with 1 mole of OH- to give 1 mole of water. This is what the question means when it asks for ΔH per mole of water formed - not the water initially present in the solutions. You need to work out the number of moles of water formed in the neutralization reaction, and divide 1465.1 J by that number. For that, you need the concentrations of the solutions, which Borek asked you for but you didn't give.
 
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