Calculating Enthalpy Change: HNO3 + KOH

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In summary: Looking" type problemsThese are the types of problems that look different when you solve them. The most common example of this is when you have a periodic table in front of you and you can't find the element you're looking for. In this case, the problem looks different because the elements are arranged in a different way. Other types of problems that can look different are problems that have more than one solution, or problems that are impossible to solve because one of the variables is missing.["In summary, "]Well up to this point, the problems have been calorimeter problems, however, at the end of the assignment has different "looking" type of problems.
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Blade
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Well up to this point, the problems have been calorimeter problems, however, at the end of the assignment has different "looking" type of problems.

i.e.
"What would the change in enthalpy, in kJ/mol, be for the reaction of 50.0 mL of 1.00 M HNO(3) with 50.0 mL of 1.00 M KOH?"
These don't give a specific heat, change in temperature, or density. Which I have been using for the previous problems. (change in enthalpy = (SH)(mass)(change in temp)) Is there something I'm overlooking? It seems simple...
[As far as I know, I'm not suppose to use anything else besides a periodic table]
 
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As far as I know, formation of inorganic salts require heat to dissolve in water; so this will be an endothermic reaction. You can confirm this reasoning by considering some cooling mixtures; in some of them, sodium nitrate is used to provide a lower freezing temperature.
 
  • #3
Let's nudge this back in the correct direction --- you've done some other "neutralization" problems? Right? Sodium hydroxide plus hydrochloric acid? Right? A neutralization reaction.

Words to the wise from Bystander: "I have no qualms about letting you be dragged off into the woods to be mugged and raped by the forces of darkness, ignorance, and superstition who prowl this forum. When I "type" (speak), you "read" (listen) and heed. When I'm silent, don't think for a minute you've got the straight dope.

chem_tr's okay, but prone to step in when he should sit back --- this is a good case in point --- no help on this question would have been better than what was offered. See the "chem guru" thread.
 
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Jeez, took me a while, but finally realized that these questions were actually connected to some previous questions *hits self on head*

So, I'm guessing this is what they stemmed out of:

1. Which I solved the rxn (47.3 mL of 2.00M nitric acid, 47.1 mL of 2.00M sodium hydroxide) change in enthalpy as -209 kJ/mol*deg

These are paired with I assume with nitric, and NaOH in portions --^
So... since enthalpy is an extensive property... it would seem to suggest that the solutions would just be proportions of the answer I determined correct?

["What would the change in enthalpy, in kJ/mol, be for the reaction of 50.0 mL of 1.00 M nitric acid with 50.0 mL of 1.00 M KOH?"

"What would the change in enthalpy, in kJ/mol, be for the reaction of 25.0 mL of 1.00 M nitric acid with 25.0 mL of 1.00 M KOH?"]
 
  • #5
Blade said:
Jeez, took me a while, but finally realized that these questions were actually connected to some previous questions *hits self on head*

So, I'm guessing this is what they stemmed out of:

1. Which I solved the rxn (47.3 mL of 2.00M nitric acid, 47.1 mL of 2.00M sodium hydroxide) change in enthalpy as -209 kJ/mol*deg

These are paired with I assume with nitric, and NaOH in portions --^
So... since enthalpy is an extensive property... it would seem to suggest that the solutions would just be proportions of the answer I determined correct?

["What would the change in enthalpy, in kJ/mol, be for the reaction of 50.0 mL of 1.00 M nitric acid with 50.0 mL of 1.00 M KOH?"

"What would the change in enthalpy, in kJ/mol, be for the reaction of 25.0 mL of 1.00 M nitric acid with 25.0 mL of 1.00 M KOH?"]

"1" gives you the enthalpy of neutralization (formation of water from H+ and OH- ) --- this is the major heat for the reaction. Generally, it is necessary to consider enthalpy of dilution for those cases in which a different final concentration occurs (1m NaNO3 in "1" differs from .5m KNO3 in two ways, concentration and cation species). Do you have dilution experiments that allow you to make such a correction? If not, you are looking at an approximation that enthalpy of dilution is negligible compared to enthalpy of neutralization.
 

FAQ: Calculating Enthalpy Change: HNO3 + KOH

What is the equation for calculating enthalpy change of HNO3 + KOH?

The equation for calculating enthalpy change of HNO3 + KOH is: ΔH = Hproducts - Hreactants. This means that the enthalpy change is equal to the difference between the enthalpy of the products and the enthalpy of the reactants.

What are the units for enthalpy change?

The units for enthalpy change are usually kilojoules per mole (kJ/mol) or joules per mole (J/mol).

How do I determine the enthalpy of a substance?

The enthalpy of a substance can be determined by measuring the temperature change during a reaction or by using standard enthalpy values from a reference table. It can also be calculated using Hess's Law or using bond enthalpies.

What factors affect the enthalpy change of a reaction?

The enthalpy change of a reaction is affected by the nature of the reactants and products, the temperature and pressure, and the physical state of the reactants and products. Catalysts can also affect the enthalpy change by lowering the activation energy of the reaction.

How can I use enthalpy change calculations in real-world applications?

Enthalpy change calculations are commonly used in industries such as food and pharmaceuticals to determine the energy requirements for reactions. They are also used in thermodynamics and heat transfer for designing and optimizing energy systems. Additionally, enthalpy change calculations are important in environmental science for understanding the energy released or absorbed in chemical reactions that affect the Earth's climate.

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