Positive and Negative
I am in the process of learning Chemistry. I find the subject fascinating, but...wow! For me, it's complicated.
So far I have got my brain around the following basic items:
That an atom is made up of smaller particles as follows:
and that the nucleus can be subdivided further into two separate items as follows:
Everything around me and including me--my computer, my brain, my hair, the earth's crust, the oceans, the sun, distant galaxies--all are made up of atoms.
Very Complicated Provisos
are what I come to ET (among other places) to learn about. DoDo pointed me to neutron stars a while back; while Martin gave me a look-see at the latest experiments they are doing on the kinds of things that appear if you smash protons and neutrons into tiny pieces--about these things I know much less than I know about chemistry, and I know very little about chemistry, so...keeping to my simpler model...
Hey, rg, why'd you choose chemistry?
Physics is too difficult (for me, at present.) I can't do the maths, and without the maths (and maybe even with it--I can't do the maths so I'm guessing), I would be pondering models...that I couldn't understand.
Biology: you start with a cell (the basic building block of life--lots of arguments there, too, intriguing ones but....)--which is made up, when examined, of chemicals such as sulphur, phosphorus, and carbon--and if I don't really understand what sulphur, phosphorus, carbon, etc. are--I have the feeling of...walking into a conversation where everyone knows the various characters they're talking about while I'm going, "Who?"
for me sits between "too complicated for me (at present) maths" and "too complicated for me (at present) aggregations".
Talking about positive and negative
Right, here's my hang up--and I want to share it here in order to receive (if possible!) your help in overcoming it.
rg's Hang Up
is with words and their historical associations. I associate the words "positive" and "negative" as follows:
"positive" = good, more, gain
"negative" = bad, less, loss
Reduction and Oxidation
Also know as "redox" is one of the things you have to know about to pass your Chemistry GCSE [UK exam for sixteen year olds]. Here's wikipedia on the subject.
Redox - Wikipedia, the free encyclopedia
Now, leaving oxidation to one side, reduction is
--a gain in electrons (well, that's a simplification but I'm at that stage in my education...)
So reduction is a gain. Right, so, following my internal map of positive and negative, a gain must be something positive, right?
Wrong! A gain in electrons means an increase in negative charge. So reduction = gain = more negative charge...
I'm stuck in morality!
As a friend said, when I explained my dilemma, "Yes, you have to lose the morality."
"I can do that," I said, "but...negative and positive are not equivalents. There is a qualitative difference. My trouble is I can't get my head around the concepts without getting lost in the idea of positive as a gain and negative as a loss."
Cathodes and Anodes
An ion is an atom that has either lost or gained an electron or electrons. A cation is an atom that is positively charged (it has lost an electron or two or three); and an anion is an atom that is negatively charged (it has gained an extra electron or two or three.)
Cathodes and anodes are....
Cathode - Wikipedia, the free encyclopedia
A cathode is an electrode through which (positive) electric current flows out of a polarized electrical device. Mnemonic: CCD (Cathode Current Departs).
Anode - Wikipedia, the free encyclopedia
An anode is an electrode through which (positive) electric current flows into a polarized electrical device. Mnemonic: ACID (Anode Current Into Device). Electrons flow in the opposite direction to the positive electric current.
(Ouch my head!)
Positive attracts negative and negative attracts positive
A cathode is giving out electrons--it is a source of electrons (=positive? No! It is giving out negative particles--it is losing electrons.)
Positive cations are drawn to the cathode because they lack electrons (lack = negative? No! Gaining more electrons is positive? Well, it's what the positive cations attempt to do--to create electrical balance--)
Yes, thank you. I understand you perfectly. (Cough cough cough cough cough!) So, what is your question?
My question to ETers is:
Can anyone offer me a mental model such that when I see
I don't immediately think, "Ah! That's the positive sign--two plus two equals five, etc.--so something positive is going on, which means some addition is happening". . .
(An atom becomes positively charged when it loses an electron)
And if I see the following sign:
I don't think "Ah! Take something away!"
(An atom becomes negatively charged when it gains an electron)
A Brief Deviation (a.k.a. Lovely Symbols)
Why anyone decided to call a "mole" a mole, I don't know. The guy--Sg. Avogadro--who is associated with the word (more in a sec) was italian, so maybe "mole" could be pronounced "moh leh", of which there is one in Torino:
(It's the big pointy building)
...but what does that have to do with atoms?
NPR: Chemistry Lovers Celebrate Mole Day
A mole is the number 6.02E23 (602000000000000000000000.) It's big, especially in chemistry where most numbers are really small. The mole is used to convert those really small numbers into something chemists can work with.
Check out that number (called Avogadro's number):
6.02 times ten to the power of 23 (which means add twenty three zeros, so):
,000 (3 zeros = thousand)
000,000 (6 zeros = million)
000,000,000,000,000 (bear with me!)
000,000,000,000,000,000,000 (that's three six nine twelve, fifteen, eighteen, twenty one zeros)
(I may be wrong by a couple of zeros!)
= the number of atoms in one "mole" of...anything.
1 gram of hydrogen has 6.02^23 atoms and = 1 mole of hydrogen
12 grams of carbon has 6.02^23 atoms and = 1 mole of carbon
40 grams of calcium has 6.02^23 atoms and = 1 mole of calcium
(If bicycles and cars were atoms, 6.02^23 bicycles would weigh less than 6.02^23 cars)
Putting 6.02^23 into context
I have heard three analogies.
If one glass of water represents one atom, then one mole of atoms (that's 602,000,000,000,000,000,000,000 individual atoms)contains more atoms than there are glasses of water in all the world's oceans
If one grain of sand represents one atom, then one mole of atoms contains more atoms than there are grains of sand on all the beaches around the UK
If a pea is taken to represent one atom (it's round, so I like this analogy!), then one mole of atoms, represented in peas, would cover the entire planet in peas to a depth of twenty kilometres.
(Or maybe it was miles--anyway, that's lots of peas!)
So, imagine the magnification if I want to look at just one atom, and then imagine the magnification if I want to look inside that atom to see the nucleus, which is one ten thousandth the width of the atom, which means if you grabbed that single pea and blew it up to be ten kilometres across (! Huge pea!) the nucleus would be one metre wide--
Did I get that right?
(10,000 metres = 10 kilometres)
So, I hold this imaginary nucleus--one metre across and made up of protons (positive) and neutrons (neutral), and around me fly electons (negative) in their various orbitals (their crazy movements around the positive centre), and those electrons farthest out (up to ten kilometres away), those that can get farthest from the one metre wide nucleus I'm holding, they're the ones that go off and do strange things that we know as chemical reactions--
O + O = O2
2C + O2 = 2CO
and one single CO is Carbon monoxide (Carbon with one oxygen):
And what holds those two atoms together is a reaction between the flying electron clouds, and to understand that, I have to understand the giving, taking, and sharing of electrons, and to do that I need to get my head around this positive and negative business in such a way that:
The qualities I ascribe to positive and negative are such that I find it easy (well, easier) to follow those + and - signs as they appear.
My Current Model
Did I tell you the model my friend suggested? Here it is:
"The positive is comfortable, it has enough, it can afford to lose an electron or two. The negative is always after a bit more, it wants to grab an extra electron or two (or even three) if it can."
But isn't it really all about charge?
Charge and forces....I feel complicated mathematical equations bearing down on me. I mean this kind of thing:
We all hold internal models of the world. The famous maps described by many, but I'll go with Robert Anton Wilson's version because I can remember where it is on the internet, and because it links into a discussion I had with francois a couple of days ago.
Here's the quote:
Robert Anton Wilson | Cosmic Trigger, Volume I
My own opinion is that belief is the death of intelligence. As soon as one believes a doctrine of any sort, or assumes certitude, one stops thinking about that aspect of existence. The more certitude one assumes, the less there is left to think about, and a person sure of everything would never have any need to think about anything and might be considered clinically dead under current medical standards, where absence of brain activity is taken to mean that life has ended.
My attitude is identical to that of Dr. Gribbin and the majority of physicists today, and is known in physics as "the Copenhagen Interpretation," because it was formulated in Copenhagen by Dr. Niels Bohr and his co-workers c. 1926-28. The Copenhagen Interpretation is sometimes called "model agnosticism" and holds that any grid we use to organize our experience of the world is a model of the world and should not be confused with the world itself. Alfred Korzybski, the semanticist, tried to popularize this outside physics with the slogan, "The map is not the territory." Alan Watts, a talented exegete of Oriental philosophy, restated it more vividly as "The menu is not the meal."
Where our mental models get stuck is when they are no longer effective to understand the realities around us. I feel that my mental model of positive and negative, when applied to the world of atoms, is not efficient. I keep making mental assumptions that only serve to confuse me when faced with something like this:
(That's...hmmm...carbon surrounded by four hydrogen atoms, each hydrogen shares its single electron with one of the carbon electrons, so the hydrogen atoms are...er...pulling in more negative energy?
If I put my mind to it I could do the chemistry without having the understanding. I would like to make an immediate analogy to a....to a person....who has beliefs contrary to the way the world works (a 6,000 years ago God made everything creationist, say), who nevertheless can negotiate the world, use chalk, light a fire and burn carbon (+ other things) in oxygen--
Two explosions, one to my centre right, ahead of me, and then another further to the right and further away. What can they mean?
With efficient and effective models I'll have a better idea of what's going on.