Lit value for standard enthelpy change of formation for aqeuous HCl

In summary, the conversation is about calculating the standard enthalpy change of formation for solid Ammonium Chloride in a lab experiment. The method involves using literature values for four separate reactions, but the literature value for the standard enthalpy change of formation for aqueous Hydrogen Chloride cannot be found. It is mentioned that this value cannot be converted from the literature value for gaseous Hydrogen Chloride. However, a solution is found by changing the sign of the literature value.
  • #1
Barfolumu
68
0

Homework Statement



This is not a problem, per se, because it is part of my Lab. We're calculating the standard enthalpy change of formation for solid Ammonium Chloride. To do this, we're using four separate rxns, and totaling their individual standard enthalpy change of formations. For two of these reactions we're using literature values, but I can not find the literature value for the standard enthalpy change of formation for aqueous Hydrogen Chloride online or in my book -- I can only find the lit value for gaseous Hydrogen Chloride. As far as I know, there is no way to convert one to the other, because these are determined experimentally, so I need to know the lit value for aqueous Hydrogen Chloride. Am I just missing something, or does anyone have a place where I can look this up?

Homework Equations





The Attempt at a Solution



Google and my textbook.
 
Physics news on Phys.org
  • #2
I'm doing this too and my lab manual says delta H for HCl (g)---> HCl (aq) = -75140 J/mol.

If you want it in the other direction, merely change the sign.
 
  • #3
workerant said:
I'm doing this too and my lab manual says delta H for HCl (g)---> HCl (aq) = -75140 J/mol.

If you want it in the other direction, merely change the sign.

doh! of course. man, i feel sheepish now. thanks.
 

1. What is the "Lit value" referred to in the term "Lit value for standard enthalpy change of formation for aqueous HCl"?

The "Lit value" in this context stands for the literature value, which is the accepted or commonly used value for a particular quantity in scientific literature.

2. What is the standard enthalpy change of formation for aqueous HCl?

The standard enthalpy change of formation for aqueous HCl is the amount of energy released or absorbed when one mole of aqueous HCl is formed from its constituent elements in their standard states at a constant pressure of 1 bar.

3. How is the standard enthalpy change of formation for aqueous HCl determined?

The standard enthalpy change of formation for aqueous HCl is typically determined experimentally using calorimetry, where the heat transfer is measured during the reaction between hydrogen gas and chlorine gas to form HCl gas, which is then dissolved in water to form aqueous HCl. The measured heat transfer is then used to calculate the enthalpy change.

4. What is the unit for the standard enthalpy change of formation for aqueous HCl?

The unit for the standard enthalpy change of formation for aqueous HCl is kilojoules per mole (kJ/mol).

5. How does the Lit value for standard enthalpy change of formation for aqueous HCl compare to the experimental values?

The Lit value for standard enthalpy change of formation for aqueous HCl is usually a theoretical value based on thermodynamic calculations, whereas the experimental values may vary due to factors such as measurement errors or differences in experimental conditions. However, the Lit value is often used as a reference point for comparison with experimental values.

Similar threads

  • Biology and Chemistry Homework Help
Replies
3
Views
1K
  • Biology and Chemistry Homework Help
Replies
10
Views
7K
  • Biology and Chemistry Homework Help
Replies
8
Views
6K
  • Biology and Chemistry Homework Help
Replies
3
Views
2K
  • Biology and Chemistry Homework Help
Replies
1
Views
1K
  • Biology and Chemistry Homework Help
Replies
1
Views
6K
Replies
2
Views
1K
  • Biology and Chemistry Homework Help
Replies
1
Views
3K
Replies
1
Views
3K
  • Biology and Chemistry Homework Help
Replies
4
Views
12K
Back
Top