Answer:
The possible valances can be determined by electron configuration and electron negativity
Good Luck even though this was asked 2 weeks ago
Explanation:
All atoms strive for stability. The optima electron configuration is the electron configuration of the VIII A family or inert gases.
Look at the electron configuration of the nonmetal and how many more electrons the nonmetal needs to achieve the stable electron configuration of the inert gases. Non metals tend to be negative in nature and gain electrons. ( They are oxidizing agents)
For example Florine atomic number 9 needs one more electron to reach a valance number of 8 electrons to equal Neon atomic number 10. Hence Flowrine has a valance of -1
Oxygen atomic number 8 needs two more electrons to reach a valance number of 8 electrons to equal Neon atomic number 10. Hence Oxygen has a valance charge of -2.
Non metals with a low electron negativity will lose electrons when reacting with another non metal that has a higher electron negativity. When the non metal forms an ion it is necessary to look at the electron structure to determine how many electrons the element can lose to gain stability.
For example Chlorine which is normally -1 like Florine when it combines with oxygen can be +1, +3, + 5 or +7. It can lose its one unpaired electron, or combinations of the unpaired electron and sets of the three pairs of electrons.
Answer:
A.
Explanation:
I forgot butt im surely it is;-)
A second-order extension of the Kohn-Sham total energy in density-functional theory (DFT) with respect to charge density fluctuations serves as the foundation for the density functional based tight binding (DFTB) approach.
What is DFTB method?
- The density functional based tight binding (DFTB) electronic structure method was used to study the clusters of bare TiO2 and TiO2 with linked organic ligands modeling polyorganic composites used as photocatalytic materials.
- The results were compared to those obtained from B3LYP/6-31G(d,p) calculations, semiempirical methods PM6 and PM7, and available experimental data.
- It was discovered that the highly scalable DFTB approach produces outcomes that are nearly on the level of theory B3LYP/6-31G(d,p).
- The trans3d set more accurately reproduces the energies of the composite material production in polycondensation processes, but the corrected version of the tiorg DFTB parameter set (tiorg-smooth) performs better for structural parameter estimations.
- The tiorg-smooth and trans3d settings perform better than the matsci set in some way. Studies of adsorption complexes of bare TiO2 clusters can be conducted using the tiorg-smooth and matsci sets.
Learn more about the Density with the help of the given link:
brainly.com/question/23487480
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