[vivekrai]

http://www.screencatch.com/view.php?i=13345047458535

[fledarmus]

For problems 2 and 3, you may want to review electrophilic aromatic substitution again, especially the effects of substituent groups. What effect does a halogen have on the rate and direction of reaction? A ketone? A methyl group? If you don't have  a source, this is a reasonable review - http://www2.chemistry.msu.edu/faculty/reusch/VirtTxtJml/benzrx1.htm

For question 4, each of the ions you show have the same electronic configuration - the Argon configuration. Consequently, the size of the orbitals will be determined by the amount of positive charge in the nucleus - the higher the positive charge, the closer the electrons will be to the nucleus and the smaller the ion will be. So which of the ions has the most protons? the least?

[vivekrai]

Hmm. Yes I get it now. Still confused for the first one. There I know that it is Fe(II), so NO is ought to be neutral .

[Borek]

I would say NO, especially in the context of the ring test chemistry:

http://en.wikipedia.org/wiki/Nitrate_test

Although NO⁺ is often listed as ligand:

http://en.wikipedia.org/wiki/Metal_nitrosyl

[juanrga]

Hmm. Yes I get it now. Still confused for the first one. There I know that it is Fe(II), so NO is ought to be neutral .

[Fe(H₂O)₅(NO)]²⁺

is the typical example of Fe(I) complex with electronic configuration d⁷. Thus the answer NO⁺ is correct.

[juanrga]

I would say NO, especially in the context of the ring test chemistry:

http://en.wikipedia.org/wiki/Nitrate_test

Although NO⁺ is often listed as ligand:

http://en.wikipedia.org/wiki/Metal_nitrosyl

Effectively, NO is generated under the conditions of the brown ring test and bonds to Fe(II) with configuration d⁶.

But in other conditions the complex of NO⁺ with Fe(I) exists.

[vivekrai]

I would say NO, especially in the context of the ring test chemistry:

http://en.wikipedia.org/wiki/Nitrate_test

Although NO⁺ is often listed as ligand:

http://en.wikipedia.org/wiki/Metal_nitrosyl

Sir, Now this thread lists two contradictory posts. Which one should I follow? I had checked with wikipedia for it to be NO, but then a friend of mine pointed out what juanrga has said.
Now what should I do?

[sjb]

I would say NO, especially in the context of the ring test chemistry:

http://en.wikipedia.org/wiki/Nitrate_test

Although NO⁺ is often listed as ligand:

http://en.wikipedia.org/wiki/Metal_nitrosyl

Sir, Now this thread lists two contradictory posts. Which one should I follow? I had checked with wikipedia for it to be NO, but then a friend of mine pointed out what juanrga has said.
Now what should I do?

I guess mentioning both possibilities is out of the question? Perhaps think about how you'd distinguish between them? (might it also be Fe(III) and NO- ?)

[juanrga]

I would say NO, especially in the context of the ring test chemistry:

http://en.wikipedia.org/wiki/Nitrate_test

Although NO⁺ is often listed as ligand:

http://en.wikipedia.org/wiki/Metal_nitrosyl

Sir, Now this thread lists two contradictory posts. Which one should I follow? I had checked with wikipedia for it to be NO, but then a friend of mine pointed out what juanrga has said.
Now what should I do?

To clarify my point. My two posts were an attempt to show that there is not contradiction between different answers. Both Fe(I) and Fe(II) complex exist. It depends of the conditions!

The answer NO⁺ given in the answer section of your 'homework' is correct, because [Fe(H₂O)₅(NO)]²⁺ is the typical example of a Fe(I) complex with electronic configuration d⁷.

At the same time, as Borek pointed out, a complex [Fe(H₂O)₅(NO)]²⁺ of Fe(II) with configuration d⁶ is formed under the conditions of the brown ring test.

[vivekrai]

In the original complex, It mentioned the brown ring complex, So the answer should then be NO ? Thanks!

[AWK]

Neutral NO form bond using its own pair of electrons hence a formal charge on N in NO is +

Hmm. Yes I get it now. Still confused for the first one. There I know that it is Fe(II), so NO is ought to be neutral .