Transition metals questions

[SmokingSkillz]

Can anyone help, I am having problems understanding reactions involving the transition metals, particularly their electron configuration and valency. I have recently learnt that each shell has subshells s, p and d.

 

What is the d subshell and is there a reason why you get electrons 2 in s, 6 in p and 10 in d.

 

Does an atom with a d shell need 10 electrons instead of 8 in it's outer shell to be inert?

 

How can the valency / oxidation number be calculated from the atomic number? is there a formula that will work for all elements?

I had been thinking along the lines of:

 

4 - (electrons % 8) which gives the number of electrons above or below inertness, but i dont think this works for transition metals.

[SmokingSkillz]

sorry 4-(electrons%8) is crap!

[YT2095]

their chemical properties are similar to those along the same period (horizontaly in D block).

the INNER shells aren`t complete tho, and so they have different valencies.compared them to the other blocks S,P and F in general.

maybe that`ll help a little?

[SmokingSkillz]

sorry but not really,

do you mean the properties of d block of same period are similar?

I thought groups usually exhibit the same properties.

 

How do you mean compare them to the s, p and f blocks arent they very different?

 

I notice that there is always 2 electrons in the outer shell for the d block atoms, does this factor contrive their properties?

[wolfson]

Well when you are taking about inert (or not), you must understand compounds (covalent) create inert gas stability, and ionic also (excluding transition metals), so back to transition metals, the best way to understand is by means that the s(orbitals) in d block elements are at lower energy states than the d subshells. As atoms always strive to be in states of lowest energy, s shells are filled up first. The copper and chromium exceptions - which have one electron in their outer orbital - do so because of electron repulsion. Sharing the electrons throughout the s and d orbitals gives lower energy states to the atoms than putting two electrons in the outer s orbital.

 

Not all d block elements are transition metals. Scandium and zinc don't qualify, due to the chemical definition given above. Scandium has one electron in its d subshell, and 2 electrons in its outer s orbital. As scandium's only ion (Sc3+) has no electrons in its d orbital it is clear that it doesn't have a 'partially filled d orbital'. Similarly, zinc is not applicable because its only ion, Zn2+, has a full d orbital.

 

So in all you need to remember is that Transition elements are chemically defined as elements which form at least one ion with a partially filled subshell of d electrons. If you need any more help on the periodic table of elements then just ask, i studied Chemistry so i should be able to help with your questions.

[SmokingSkillz]

thanks, Its still is a little hazy, surely there should be no gaps in the lower shells as the atom will have less energy.

 

What is considered a to be a full d-shell i have seen atoms with between 9 and 18 that also have a couple of electrons in f.

 

Is there a way to determine the number of bonds the transition metals will create?

 

Francium has a load of electrons in lower states and one in the outer shell so why is it not in the same group as copper or chromium?

[YT2095]

the further away from the nucleus the outer electron is, the easier it is to ripped away (less nuclear forces holding it in place).

Fr. fit`s that bill perfectly

[SmokingSkillz]

I was wondering if you excite an atom with photons will it's properties change as the electron configuration is different?

[wolfson]

The resulting molecular orbitals are not as tightly defined as in an atom due to variations in bond behavior. This bond variation results in a broadening of the energy levels for each excited state and molecules have broad absorption bands. In addition, a complex molecule can have multiple excited states that result in light absorption at multiple wavelengths.

[YT2095]

Wolfson, that sounds like Quote from somewhere almost

 

 

SmokingSkillz said in post # :

I was wondering if you excite an atom with photons will it's properties change as the electron configuration is different?

 

 

Photons will not directly effect elemental atoms per se, they can however be used as the "trigger" or energy used to stimulate a reaction, known as "Activation energy", all reactions require activation energy, some levels being lower than others, hence the use of catalysts in reactions, it lowers the "Activation Energy" for a reaction to take place

[SmokingSkillz]

YT2095 said in post # :

their chemical properties are similar to those along the same period (horizontaly in D block).

the INNER shells aren`t complete tho, and so they have different valencies.compared them to the other blocks S,P and F in general.

maybe that`ll help a little?

 

so can the valencies be woked out based on the number of electrons?

[wolfson]

Yes thats easily done, by just looking at how many electrons(-) the element want to loose or gain remember OIL RIG.

 

Oxidation is LOSS

 

Reduction is GAIN

 

Thus:

 

Group number 1 2 3 4 5 6 7 8

Valency 1 (+) 2 (+) 3 (+) 4 (+) 3 (-) 2 (-) 1 (-) 0 (na)

[chemistry]

"What is the d subshell and is there a reason why you get electrons 2 in s, 6 in p and 10 in d."

 

The rules are due to limitations mentioned in quantum mechanics. 2 electrons can exist in an orbital, an orbital. A subshell (s,p,d etc...) has a specific number of orbitals; and has specific "shapes" for these orbitals. A subshell is inclusive of a shell.

 

"Does an atom with a d shell need 10 electrons instead of 8 in it's outer shell to be inert?"

 

Transition metals usually form coordination complexes. Yes, elements with 10 or 5 electrons tend to be more inert than others due to stability; having all five d orbitals filled, paired or unpaired...depending on the complex in question (e.g. octahedral complexes) tend to repel ionic arrangements.

 

"How can the valency / oxidation number be calculated from the atomic number? is there a formula that will work for all elements?"

 

For most elements various oxidation numbers can be found in nature. Elements may take on different oxidation states according to the stability of a complex which suffices for the oxidation state for example. However, an element by itself with the same number of protons as electrons has an oxidation state relative to noble gases.

 

hope this helps

 

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[SmokingSkillz]

thanks all, I think i am getting there. I have bought a good chemistry book (principals of chemistry), but not got that far yet!

[Radical Edward]

YT2095 said in post # :

Wolfson, that sounds like Quote from somewhere almost

 

http://sunflower.bio.indiana.edu/~rhangart/courses/b373/lecturenotes/photomorph/light.html

 

(quotes need references plz, rather than passing stuff off as your own)

[wolfson]

Incorrect, its actually Ouellette, a great chemistry book, I actually thought that most Chemist would have known the quoye, so I do appolagise, and I actually NEVER quote from a website, i only insert links, thats uni that drills that into you.

 

Ouellette, p125, (1998), 3rd edition, New York.