Bonding of Diamond: Unreactivity & Impurity

[jadelamlam]

Homework Statement

Hi,
there are 2 pictures in the above,pic 2 shows a diamond in rectangular shape.
pic 1 shows the 3D structure of that diamond at a corner of it.
As we know,diamond has a giant covalent structure,which means atoms in it are linked together by covalent bonds only.
Now,please see the pink circle,3 electrons of that carbon atom are covalently bonded to 3 other carbon atoms.
Each carbon atom has 4 outermost electrons.Where is the remaining electron?

Homework Equations

The Attempt at a Solution

Is it forming a covalent bond with another element?(e.g.oxygen in the air)
If not,it should be reactive due to the unbonded electron but in fact diamond is unreactive.
From the above deduction,there is no diamond with 100% purity(i.e.no impurities)?

just a guess :)

Please help,thx :)

 

[AGNuke]

There is nothing with 100% purity. You can approach to one, like 99.9999...%, but no 100%.

 

[TLChenhall]

I don't remember much chemistry, but I have done some programming imaging various 2D / 3D tilings & 3D / 4D lattices as Pascal's Triangle like structures. A suppositional electron?

https://sites.google.com/site/pascalloids/home