If there are six water molecules in the inner-sphere hydration shells of both Na+ and Al3+, how much of the standard free energy of hydration can be accounted for by inner-sphere hydration?
Standard Free energy of hydration, Delta G=-164\ z^2 +1.3\{kcal}{mole};
r’cation = cation radius + 0.72 Å
r’anion = anion radius + 0.3-0.6 Å
z is the charge of the ion
Does anyone have an example of how to solve this problem?
Any help, pls
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Re: Any help, pls
To calculate the standard free energy of hydration for inner-sphere hydration, we can use the following equation:
Delta G = -164 * z^2 / r + 1.3
where z is the charge of the ion, r is the radius of the ion in angstroms, and Delta G is the standard free energy of hydration in kcal/mol.
For Na+ and Al3+, we know that there are six water molecules in the inner-sphere hydration shells. Using the ionic radii for Na+ and Al3+ (1.02 Å and 0.54 Å, respectively), we can calculate the radius of the hydrated ions as follows:
r’cation = cation radius + 0.72 Å
For Na+, r’cation = 1.02 + 0.72 = 1.74 Å For Al3+, r’cation = 0.54 + 0.72 = 1.26 Å
Using these values, we can calculate the standard free energy of hydration for inner-sphere hydration for Na+ and Al3+ as follows:
Delta G(Na+) = -164 * 1^2 / 1.74 + 1.3 = -93.8 kcal/mol Delta G(Al3+) = -164 * 3^2 / 1.26 + 1.3 = -1,080.5 kcal/mol
Therefore, the standard free energy of hydration that can be accounted for by inner-sphere hydration for Na+ and Al3+ is approximately -93.8 kcal/mol and -1,080.5 kcal/mol, respectively.
Delta G = -164 * z^2 / r + 1.3
where z is the charge of the ion, r is the radius of the ion in angstroms, and Delta G is the standard free energy of hydration in kcal/mol.
For Na+ and Al3+, we know that there are six water molecules in the inner-sphere hydration shells. Using the ionic radii for Na+ and Al3+ (1.02 Å and 0.54 Å, respectively), we can calculate the radius of the hydrated ions as follows:
r’cation = cation radius + 0.72 Å
For Na+, r’cation = 1.02 + 0.72 = 1.74 Å For Al3+, r’cation = 0.54 + 0.72 = 1.26 Å
Using these values, we can calculate the standard free energy of hydration for inner-sphere hydration for Na+ and Al3+ as follows:
Delta G(Na+) = -164 * 1^2 / 1.74 + 1.3 = -93.8 kcal/mol Delta G(Al3+) = -164 * 3^2 / 1.26 + 1.3 = -1,080.5 kcal/mol
Therefore, the standard free energy of hydration that can be accounted for by inner-sphere hydration for Na+ and Al3+ is approximately -93.8 kcal/mol and -1,080.5 kcal/mol, respectively.
- BerthaKelley
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Re: Any help, pls
I can't post my tutorial. Errors are continuously reported. I did not use images nor special symbols.
Re: Any help, pls
Can you please check my messages?BerthaKelley wrote: ↑Thu Dec 14, 2023 1:49 am I can't post my tutorial. Errors are continuously reported. I did not use images nor special symbols.
Re: Any help, pls
Al3+ inner-sphere hydration can account for the standard free energy of hydration of aboutBerthaKelley wrote: ↑Thu Dec 14, 2023 1:49 am I can't post my tutorial. Errors are continuously reported. I did not use images nor special symbols.