The element sodium (11 protons) has just one electron in its valence shell. The 1 and 2 shells are full, and there's one lonely electron in the 3rd layer.

Fluorine (9) has an outer shell that is not quite full, with seven ( shell limit 8) electrons.

Considering the maximum that will fit in a valence shell, sodium kind of has one extra electron, while fluorine is short one.

So we have valence shells that are almost full, versus almost empty. I gather one wants to give it away, the other takes.

How does this contrast affect the reactivity and traits of an element?

This is a picture of the "halogens" :

https://www.google.com/search?q=fluo...hVict8KHd0ZD-g

The left side of the periodic table will display the metals including sodium.


One could say that the halogens are volatile grouping whereas the metals display a different character, which I cannot clarify. In the metals are potassium, calcium, sodium , and others. these elements really do appear different as calcium and potassium differ as per example calcium readily dissolves in water whereas if potassium is pitched into water it will cause an explosion. lol potassium.

The concept is called "electronegativity." Elements towards the top right of the periodic table really want electrons, elements toward the bottom left really want to give them up.

So fluorine has a real hard time existing as F2 - it will rip electrons from wherever to form 2 F-. Likewise molecules like bleach which have an O-Cl bond will rip electrons from carbons and hydrogens in bacteria.

Sodium chloride (table salt) is really stable because sodium loves to give up its extra electron and chlorine loves to get one extra electron.

And weird things happen in the middle. Hydrogen usually prefers to give up an electron and become H+, but if potassium is around, potassium will force an electron onto hydrogen and form H- (hydride). Hydride grabs an H+ from water to make H2 gas, which is why potassium in water often pops/explodes.

https://en.wikipedia.org/wiki/Chemical_bond

https://en.wikipedia.org/wiki/Valence_bond_theory

https://en.wikipedia.org/wiki/Electronegativity



Try a course why not

https://www.youtube.com/watch?v=YkYe...0xbgZVZibxj4rb




or that

https://www.youtube.com/watch?v=iWZD...f323DiuR7-Mgir


and notes

https://ocw.mit.edu/courses/chemistr...lecture-notes/

Hey cali, is this a good place to remind you of my question from a while back?:

when acid dissolves into an aqueous solution and metal is introduced, a chemical reaction takes place. What does it look like on the micro scale?

I ask because I'm wondering what would happen if we could stop time and look at the reaction.

a) the H+ free proton will react with the loose electrons of the metal at a rate dependent on the molarity of the solution and the number of H+ cations per molecule released into the solution.

or?:

b) it's more wave like in nature and it's an electromagnetic mess which isn't as easily comprehended by humans.

or both?

It looks really really small.

It's complicated because you don't have homogeneous solutions of the metal. You have a solid metal surface with a coating of metal cations around it, the metal cation layer is sloughing off into solution exposing the metal.

Metals like Na and K react one electron at a time. So you may end up with H. (neutral hydrogen with one electron) which further reacts with H2O to give H2 and OH. (neutral radical species), etc.

The nature of the surface itself matters. The greater the surface area, the faster the metal reacts. If you have a big chunk it takes forever to react. Microscale crevices can greatly accelerate the reaction (the same way that Mentos accelerate the offgassing of Diet Coke).

These sorts of surface-solution reactions are very important in atmospheric chemistry. One of the huge breakthroughs in the field was when scientists discovered that small ice crystals floating in the polar atmospheres greatly accelerated the decomposition of ozone. That would probably be a good place to start Wikipediaing if this sounds interesting to you.