Predicting Bond Enthalpy Trends for Atom-Hydrogen Bonds

  • Thread starter Thread starter ReidMerrill
  • Start date Start date
  • Tags Tags
    Bond Periodic
AI Thread Summary
The discussion centers on identifying trends in bond enthalpy, specifically for atom-hydrogen bonds, based on calculations performed using Gaussian software. Participants note that while the original poster seeks a trend, the calculated bond enthalpies should provide insights into any existing patterns. It is suggested that for main group elements, bond dissociation energies (BDEs) typically decrease down the periodic table and increase across it. In contrast, for transition metals, M-H BDEs tend to increase down the periodic table, but a clear trend across the periodic table is less evident. A reference table is provided to assist in understanding these trends.
ReidMerrill
Messages
65
Reaction score
2
Is there a period trend for bond enthalpy? Specifically Atom-Hydrogen bonds. Need to find a trend in predicting the bond enthalpy of several atom-hydrogen bonds I calculated using gaussian.

Any help would be appreciated, thanks!
 
Chemistry news on Phys.org
ReidMerrill said:
Need to find a trend in predicting the bond enthalpy of several atom-hydrogen bonds I calculated using gaussian.
If you calculated the bond enthalpies, wouldn't you be in a better position to tell us the trend, rather than us telling you?
 
TeethWhitener said:
If you calculated the bond enthalpies, wouldn't you be in a better position to tell us the trend, rather than us telling you?
I just wondered if there was supposed to be a trend since they don't appear to follow any pattern.
 
Try this table. https://labs.chem.ucsb.edu/zakarian/armen/11---bonddissociationenergy.pdf

For maingroup elements, E-H BDE's are fairly predictable: decrease down the periodic table, and increase across the periodic table.
For transition metals, M-H BDE's increase down the periodic table (1st < 2nd < 3rd). There's not really a clear trend across the periodic table.
 
Thread 'How to make Sodium Chlorate by Electrolysis of salt water?'
I have a power supply for electrolysis of salt water brine, variable 3v to 6v up to 30 amps. Cathode is stainless steel, anode is carbon rods. Carbon rod surface area 42" sq. the Stainless steel cathode should be 21" sq. Salt is pure 100% salt dissolved into distilled water. I have been making saturated salt wrong. Today I learn saturated salt is, dissolve pure salt into 150°f water cool to 100°f pour into the 2 gallon brine tank. I find conflicting information about brine tank...
Engineers slash iridium use in electrolyzer catalyst by 80%, boosting path to affordable green hydrogen https://news.rice.edu/news/2025/engineers-slash-iridium-use-electrolyzer-catalyst-80-boosting-path-affordable-green Ruthenium is also fairly expensive (a year ago it was about $490/ troy oz, but has nearly doubled in price over the past year, now about $910/ troy oz). I tracks prices of Pt, Pd, Ru, Ir and Ru. Of the 5 metals, rhodium (Rh) is the most expensive. A year ago, Rh and Ir...
Back
Top