Please help with 3 problems on destroyer OCHEM

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STACM

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Hi, there are three problems on destroyer I just cant wrap my head around, so any help would be appreciated. They are:


163) Which resonance form would be predicted to be most stable?

--->It says the answer is B because all the atoms have stable octets, but how does N+ have a stable octet? I thought the + means it doesnt...or does the absence of a lone pair mean it has a stable octet?



169)
Complete the product:

---> I dont understand how Cl2/H2O does what it does in this problem, can anyone explain that, or what it is?


170)
Consider the Gabriel synthesis below:

---> I understand this problem up until it gets to NH2NH2 Ethanol/Heat. How does this one work?

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Hi, there are three problems on destroyer I just cant wrap my head around, so any help would be appreciated. They are:


163) Which resonance form would be predicted to be most stable?

--->It says the answer is B because all the atoms have stable octets, but how does N+ have a stable octet? I thought the + means it doesnt...or does the absence of a lone pair mean it has a stable octet?



169)
Complete the product:

---> I dont understand how Cl2/H2O does what it does in this problem, can anyone explain that, or what it is?


170)
Consider the Gabriel synthesis below:

---> I understand this problem up until it gets to NH2NH2 Ethanol/Heat. How does this one work?


164) Answer B is correct because the Nitrogen has 8 electrons forming a stable octet. I'm not sure how to correctly put this in ochem terms, but the way I interpret +'s is you count each bond has 1 e- and you get 4 electrons instead of it's original 5 so it's short 1 e-. However, since there are 4 bonds (times 2) you have a stable octet, making it the most stable.

169) I'm pretty sure that's just a formula you need to know. It's adding ortho/para at the activating group NH2.

170) NH2NH2 is just using Wolf Kishner. This is also one of those basic formulas you need to just memorize =\ ugh! I would just look up more examples online if you want to fully understand the concepts. gluck studying!
 
Cl2 H2O i was just looking at it and also had a problem. Br is a ortho and para deactivator and NO2 is a meta deactivator. So which one wins, where should you place the Cl's? Anybody?
With question number 170- as mentined its a wolf-kishner reaction- which is a complete reduction of carbonyl compounds to methyl groups upon heating wiht hydrazine hydrate and base.
 
If you wanna chose between Br or NO2. The Br wins
But choosing between Br or NH2. NH2 wins
Priority list
O/P directors & activating: ex. NR, NH2, NHCOR, OH, OR, OCOR, R >
O/P directors but deactivating: halogens >
Meta: ex. N02, So3H, CooH, COR etc...
 
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