Is Zn(OH)2 amphoteric in aqueous solution if so why?

Hello, see if this helps

An amphoteric substance is one that can display both acidic and basic properties, so look:

2NaOH + Zn(OH)2 Na2[Zn(OH)4] - to show it has acidic properties
and Zn(OH)2 + 4HCl ZnCl2 + 2H2O - to show it has basic properties.

I just am having a really hard time understanding how many electrons Zinc can hold.  Does it follow the octet rule what is its formal charge?  I believe an ionic bond occurs, I am not sure if the octet rule or similar rule applies.  Earlier today I was studying NH4Cl which amazed me because Nitrogen's outer valence can only hold 8 electrons and Cl's valence can only hold 8 electrons yet they are considered bonded (NH4Cl) because ammonium has a partial positive formal charge and chloride has a partial positive, how can Nitrogen bond when it already has a full valence?  So in this case Zinc which I believe as a metal is forming partial charges with OH- (ions, correct)?  What is the limit on Zinc's capacity for OH-? 

Both of you guys proved very adequately that Zn(OH)2 is amphoteric, but I really don't get how Zinc binds at all.  I have made numerous internet searches just to see a picture of zincs binding.  Just where do the electrons go?  SiteTester that was a novel approach that I believe that I can use in other problems.  And EmHen your article clearly states that Zn(OH)2 is amphoteric.  Thank you! 

But I am still in the dark in understanding zinc.  I know this is supposed to be a simple question and answer forum, but I am still confused and for the sake of learning could you help me understand zinc's bonding scheme!

Zinc hydroxide is amphoteric, dissolves in acids and alkalies.

http://books.google.ca/books?id=SagaBQAAQBAJ&pg=PA127&lpg=PA127&dq=%22zinc+hydroxide+is+amphoteric%22&source=bl&ots=cT4e2nr2mt&sig=hrCM1S-JfCQE0fzFgpkHH0puWZg&hl=en&sa=X&ei=rk52VI6JN8yyogTQvoDAAw&ved=0CCYQ6AEwAg#v=onepage&q=%22zinc%20hydroxide%20is%20amphoteric%22&f=false

http://books.google.ca/books?id=6y3ZAgAAQBAJ&pg=PA82&lpg=PA82&dq=%22zinc+hydroxide+is+amphoteric%22&source=bl&ots=EqZb5GF3V5&sig=MlLBL7Z8x_7CPwu5XlqN-ZOZjqc&hl=en&sa=X&ei=rk52VI6JN8yyogTQvoDAAw&ved=0CCMQ6AEwAQ#v=onepage&q=%22zinc%20hydroxide%20is%20amphoteric%22&f=false