Wikipedia:Reference desk/Archives/Science/2006 November 28

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November 28 edit

Biological pollutants in Human Waste edit

Can someone please name Biological(Living) pollutant in human waste. I would also greatly appreciate to know some of the problems it causes. I would like an answer by Wednesday the 28th of November 2006 at 11:30 am NZST. Many thanks, and ,once again, ANY help would be greatly appreciated. Cheers:

CODY NIXON-MEAD WHANGAREI BOYS HIGH SCHOOL WHANGAREI NEW ZEALAND

See E. Coli, gut flora, and fecal-oral route. --Bowlhover 00:31, 28 November 2006 (UTC)[reply]

quickest way to lose weight edit

what is better for you and what is the quickest way to lose weight? by working out or by not eating or by dieting

Arguably working out. It'll improve your cardiovascular health as well as allowing you to reduce your weight, but depending on how much you eat, you might have to diet to a degree as well. Sockatume 04:37, 28 November 2006 (UTC)[reply]
I suppose the quickest way is by not eating (health hazaards apart). A combination of workout and diet is supposed to be ideal. But in this method, quickest would be in terms of months. See http://health.howstuffworks.com/diet.htm for a good article on this. -- WikiCheng | Talk 06:59, 28 November 2006 (UTC)[reply]
"If requesting medical advice ask a Doctor instead." Methods of weight loss qualify as medical advice. Go see your doctor please. We are not responsible if you starve yourself to death because someone on Wikipedia suggested it. pschemp | talk 07:07, 28 November 2006 (UTC)[reply]
Ah, common, saying that excercise will reduce someone's body weight is medical advise? You've got to be joking. And unless you've got some health problem fasting is no serious threat. Muslims do it every year (and some Christians may still, too). And I've done it once, not eating at all for five days. In India it is said that cleans the body. One has to make sure to drink lots of water, though. And the effect will be very slow. I lost 10kg that way, but that took several months. I suppose one important reason was that my stomach had shrunk and therefore it was easier for me to eat less without getting hungry. DirkvdM 07:27, 28 November 2006 (UTC)[reply]
Yeh, I have to agree, If your going to be perdantic, you could say this is a reference desk, not a random facts hub, and reject all questions that arent asking to be referenced to an article. Bu luckily, most of us arnet that bad. Philc TECI 18:52, 28 November 2006 (UTC)[reply]

Lose 15 pounds in mere seconds! Raul654 07:34, 28 November 2006 (UTC)[reply]

Aahhh ! See also Dismemberment -- WikiCheng | Talk 09:06, 28 November 2006 (UTC)[reply]
Have you lost your head Raul? 211.28.131.37 12:10, 28 November 2006 (UTC)[reply]
  • Not eating will lose weight the fastest, but it's not healthy at all. If you want to lose weight you have to use more calories than you're eating which, unfortunately for you, means excercise. It doesn't have to be traditional excercise in a gym, though. You can take the dog for a longer walk, or do less driving and more walking. - Mgm|(talk) 08:54, 28 November 2006 (UTC)[reply]
Oh, and a reminder quickly and healthily are usually mutually exclusive when it comes to losing weight. Your body will have less trouble adapting if it goes slow. - Mgm|(talk) 08:55, 28 November 2006 (UTC)[reply]

Go do a death march. Thousands had done it and they all lose weight. 211.28.131.37 12:03, 28 November 2006 (UTC)[reply]

Go to the moon? Lose 5/6 of your weight. Neil Armstrong did it. 211.28.131.37 12:08, 28 November 2006 (UTC)[reply]

Got an extra wad of cash laying around? You could buy this and do it in your own home! 192.168.1.1 5:49am, 28 November (PST)

Quickest ways to lose weight:

  • Have a baby.
  • Amputate excess body parts.
  • Have liposuction.

StuRat 07:46, 29 November 2006 (UTC)[reply]

Well, I'll weigh in here with something that I haven't seen mentioned yet. Dieting alone tends not to be very helpful with regards to weight loss because the body changes its metabolism in response to what it perceives as "starvation" conditions. This is why crash diets lead to a yo-yo effect - any slip you make in the diet really hits you hard, then you have to work even harder to get back the ground you lost. A slow, steady decrease in caloric intake combined with a similarly slow steady increase in physical activity is your best bet. Depending on your eating habits, you may end up actually eating more to give you the energy you require to do all that new physical activity. Matt Deres 18:02, 30 November 2006 (UTC)[reply]

biology edit

what are the factors that affect the structure of a community?

Define factors, structure and community and please sign your posts:) If i was to take a guess as to the things that you mean I would say climate, education, wealth and culture are some significant things that affect the structure of a community. Vespine 06:06, 28 November 2006 (UTC)[reply]

Topic on Consumer Awareness edit

Sir,Good Morning,

I need topic on Consumer Awareness with some photograph.

With Warmest Regards M B Thapa email:removed

Consumers_International has some info -- WikiCheng | Talk 07:35, 28 November 2006 (UTC)[reply]

I'm an engineering student, so I would a voluenterrer to answer the following question for me.

The question are:

1. What are the uses of Rotary Cams?.

2. In what machinery are cams found?

3. What materials are used in maiking rotary cams and why?

4. When a Cam is rotating, what wears the most, the cam or the cam follower?

I will need pictures of the component that uses cam.

Thanks.

Marcel

See cam for some info. See http://auto.howstuffworks.com/camshaft.htm also. More info can be found in your text book, I suppose? -- WikiCheng | Talk 09:13, 28 November 2006 (UTC)[reply]
All cams rotate, so "rotary" here is otiose.--Shantavira 13:43, 28 November 2006 (UTC)[reply]
May not be. There are electronic cams which don't have any rotating parts. The opening and closing are controlled electronically for accurate timings. I suppose that the F1 racing cars us this kind of cams -- WikiCheng | Talk 15:02, 28 November 2006 (UTC)[reply]
I think they are called 'electronic (poppet) valves' - see camless (they don't use cams)83.100.158.227 15:29, 28 November 2006 (UTC)[reply]
You can also get linear cams. 80.169.64.22 16:30, 29 November 2006 (UTC)[reply]

BEARING edit

Dear Sir,

I have a question for my school project.

THE PROJECT GOES LIKE THIS.

A PDN two bearing arrangement housing (110mm shaft diameter) were installed on underground water pump for a mining industry. The engine that drives the shaft expirienced a 170% over-speed for 30minutes. This resulted in a partial meltdown of the bearing and unfortunately melted the bearing to the shaft. An inspection revealed a destroyed bearing and minimal damage to the shaft. But space is limited, the housing cannot be removed and the pump impeller cannot be removed to remove the shaft.

THE PLAN NOW IS TO REMOVE THE BEARINGS FROM THE HOUSING AND REPLACE THE BEARING WITH SPLIT CAGE BEARING MANUFACTURED BY COPPER.

THEN THE QUESTIONS ARE:


1. WHY A SPLIT CAGE BEARING IS USED FOR THIS PROJECT

2. WHAT OTHER THREE METHODS THAT MAY HAVE WORKED

3. WHAT MATERIALS WERE CHOSEN AND WHY

So I will be glad if you can assist me with the answer.

Thanks in anticipation. [[--Marcelaokafor 08:59, 28 November 2006 (UTC)Marcel]]]][reply]

Well, I'm not going to do your homework for you unless I get your grade too. But here are some things for you to think about that will set you on the right path... a normal bearing is a single piece shaped like a torus, right? Now since you can't remove the pump or the impeller, per the problem statement, you won't be able to install the new bearing over the pump shaft. You need access to one end of the shaft in order to slide the hole in the center of the bearing over the shaft, right? So what is a split bearing? Did your instructor or your textbook cover that? Can a split bearing maybe be made out of two halves, which are assembled in place? Could that be an advantage of a split bearing in this case? As to why it is copper, think about copper for a bit, it's pretty soft, right? Like you can bend a copper wire, but a steel wire would be a lot harder to bend, wouldn't it? The pump shaft is made of steel, so why would the bearing be made out of something softer? 192.168.1.1 5:38am, 28 November 2006 (PST)
In other cases a new bearing made of Babbitt metal might have been created in place. This might be one of your other 3 methods. Edison 18:22, 28 November 2006 (UTC)[reply]

How do you make friends?100110100 11:48, 28 November 2006 (UTC)[reply]

Answered on the Misc Reference desk. Please do not double post. — QuantumEleven 12:28, 28 November 2006 (UTC)[reply]

You'll need about 100-200 lbs of body parts, lots of suture thread, and a thunderbolt. :-) StuRat 07:40, 29 November 2006 (UTC)[reply]

URGENT! What do you call the test to determine whether one is a suitable bone marrow donor? edit

Is it a HLA test?

Yes. See bone marrow transplant.--Shantavira 13:46, 28 November 2006 (UTC)[reply]
Thanks. Just wanted to confirm.
...good luck on the surgery, doc

Fish deuterostomic or Protostomic edit

Are fish deuterostomic or Protostomic? i am a student an di cant find it anywhere please help?

thank you guys =]—Preceding unsigned comment added by 70.151.119.66 (talkcontribs)

I agree with the student above i need to know too i am 23 adn attend ASU..not that this is not homwork just a simple question
Are fish deuterostomic or Protostomic?
thanks—Preceding unsigned comment added by 70.151.119.66 (talkcontribs)
See Deuterostome and Protostome. This is an encylopedia, so you can look up the answer yourself by just typing the word in, in the little seach box. Good luck! X [Mac Davis] (DESK|How's my driving?) 15:43, 28 November 2006 (UTC)[reply]
Hint: the answer is Deuterostome. Neil916 (Talk) 07:39, 30 November 2006 (UTC)[reply]

Nice shoulders edit

Two girls told me I have nice shoulders. What the hell does that mean? I'm assuming it's not my idea of nice as in "large, round, and tear drop-shaped." Muscular? Or does it have to do with the infamous torso width:waist width? Or is it purely psychosomatic? X [Mac Davis] (DESK|How's my driving?) 15:44, 28 November 2006 (UTC)[reply]

I think only they can answer that, as I have not found a picture of your shoulders. Post a pic and perhaps someone here will be able to help.--Shantavira 15:51, 28 November 2006 (UTC)[reply]
Nah...that isn't necessary. The mind is abstract enough that it can read anything into everything. :-) --HappyCamper 17:44, 28 November 2006 (UTC)[reply]
It means you fulfill some (but not necessarily all) of their criteria for giving you a...
83.100.158.227...you trailed off there. Now, what might your abstract mind be thinking? --HappyCamper 19:32, 28 November 2006 (UTC)[reply]
They were probably trying to lure you back to their lair to suck out your blood, since most women are blood sucking vampires. Next time this happens, make a sign of the cross with your fingers and run for your life! ;)Vespine 22:00, 28 November 2006 (UTC)[reply]
What? An Athiest cross? X [Mac Davis] (DESK|How's my driving?) 02:39, 29 November 2006 (UTC)[reply]

Most women like wide, square shoulders. StuRat 07:37, 29 November 2006 (UTC)[reply]

Sources, please! ☢ Ҡiff 15:36, 29 November 2006 (UTC)[reply]
If you seriously want sources, this was from a program on PBS, I believe from the BBC, which looked at different physical aspects of sexual attraction in humans. I don't recall the program name. Most of their conclusions were obvious, however, like that men like rounded features on women. One surprise was that women like ultra-masculine men (rather Neanderthal-looking) when fertile, and prefer normal looking men the rest of the time. It might be one of these: [1] [2] StuRat 21:49, 29 November 2006 (UTC)[reply]

Energy to make a wind turbine. edit

Anyone know how much energy it takes to make and erect a wind turbine??? How long does it take until they have made up for this energy used? --86.139.127.29 16:29, 28 November 2006 (UTC)[reply]

It would depend a lot on the exact make-up of the wind turbine and its tower. You'll need copper and steel for the alternator, glass-reinforced plastic, carbon-reinforced plastic, wood, or aluminium for the blades, various materials for the gears, bearings, and housing, steel or wood for the tower, and copper or aluminium and more plastic for the connecting wires.
A microturbine mounted on an existing building obviously needs less material than a turbine on the scale of the Altamont Pass turbines, but also produces less energy. It'd probably be pretty difficult to calculate the exact energy payback time, but if you choose one or two configurations, maybe we can take a SWAG at it.
Atlant 17:31, 28 November 2006 (UTC)[reply]
I'd say it'd abe very difficult to come up with a precise ansswer. The problem with comming up with an answer is in part the problem of where to define the limits of a system - in this case the limits of what constitutes the "system" making wind turbines. Do you just count the cost of the manufacturer? How about the cost of building the factory? The tools? Mining ore and transprort? Educating and the welfare of workers? Installation? You need to define the system so it has an end, but as it is a product of society the absolute true cost is nearly incalculable. Another problem is defining what is a wind turbine. I imagine it costs more in energy to build a 3MW tower turbine than a 100W wind jig I can put on my shed - and they will have different efficiencies in power production. A specific turbine will vary in power generation efficiency based on the strength of the wind, current state of maintenance, humidity and quality of installation. And then do you only count the power generated or do you deduct for losses in the utilization of that power? So, the S.W.A.G. approach is probably the best you can do - but you'll still need to define your limits and terms. Robovski 03:34, 29 November 2006 (UTC)[reply]
If we simply trapped the birds the wind turbine would have killed and attached generators to their winds, what would the net benefit be? Exclude the cost of worms for now. --Tbeatty 04:33, 1 December 2006 (UTC)[reply]

"Market" for leptin edit

I suppose there could be a market for synthesized ghrelin because a lot of people are overweight and something that induces satiety could aid in weight loss for such people. But could there be a market for leptin? I'm thinking maybe for wasting disease such as end stage cancer or AIDS. Are there more "markets" than these two for leptin? Jack Daw 16:46, 28 November 2006 (UTC)[reply]

First, I think you have your hormones mixed up. Leptin stimulates satieity (reducing hunger) and ghrelin turns off that satieity signal, effectively stimulating hunger. With the exception of patients with congenital leptin deficiencies, increasing leptin in the body does not typically alter eating patterns in the long term, with the added problem that exogenous dosage can lead to leptin resistance. Ghrelin may well be an effective antianorectic, but there are many other chemicals which already do this. Also, reduced feeding is not typically due to reduced hunger, but the presence of nausea (as in the AIDS and ES Cancer patients you mention above), or another inhibitory influence (as in anorexia nervosa). Tuckerekcut 01:13, 29 November 2006 (UTC)[reply]

detailed information regarding the physics of webbed feet in birds, especially as it relates to birds which skim on the water as it lands edit

Dear Wikipedia,

I am looking for more detailed information about the physics of webbed feet in birds, especially as it relates to bird’s which skim on the water as it lands.

The type of information I am seeking has to do with the relationship of the birds weight to the surface area of the feet. Knowing enough about physical science, I assume there must be an overall relationship to webbed feet birds that use the webbed feet for skimming on the water when they land in the water to the total area of the webbed feet. Of course, the webbed feet also provide greater ability for locomotion on and within the water, but as any bird will tell you, webbed feet are very “handy” to use when landing ON the water.

Can you guide me to information regarding the mathematics, relationships, physics, or any empirical studies done on the ratio/proportions of webbed feet to body mass of birds which skim on the water when landing? If only such information regards propulsion on and within water…then I’ll take that.

Thank you

Carson tb124 at earthlink.net

I sent an E-Mail to your address with the best available answer given due to the necessity of the bird, and considerations of their feet. Most birds are private in the matters of their webbing, yet the answer should be enough to fulfill the curious.

The abuses of silicates edit

Silica is the basis for many things positive, yet the introduction into the human body has no advantages. There are the biblical aspects of "'gates of death"' that are computer chip implementations which I have deemed the new form of enslavement within America, and there is the base element of most medications Si. My question is this, " How can any person of science, who has achieved the ability of reason based upon fact, believe silicates are positive in the foods and medications when they are plastics, rubbers, glasses, and rocks? I would appreciate an unbiased opinion that has been formed through research without predjudice. John Wesley Blum

The second clause of your second sentence is unintelligible, yet at least linguistically your question seems to depend on it for sense. Can you clarify what "there is the base element of most medications Si" is intended to mean? Then maybe we can tackle your question. alteripse 19:31, 28 November 2006 (UTC)[reply]

Translation: "Silicon is common in most medications". (I don't know if this is true or not.) StuRat 07:24, 29 November 2006 (UTC)[reply]

(edit-conflict} Coupla major problems obviate the need even to do research yet:

  1. Technical issue: computer chips are not usually made of silicates.
  2. Huge logical falacy: your logic would also support avoiding oxygen (present in plastics, glasses, rocks, maybe some synthetic rubbers), carbon (present in plastics, rocks, rubbers), and hydrogen (present in plastics, glasses, rubbers, rocks).
  3. Faulty premise: silicon is not present in most medications, or if it is, only as an inert filler that could easily be avoided by reformulation.

DMacks 19:32, 28 November 2006 (UTC)[reply]

Silicic acid might interest you. --HappyCamper 19:45, 28 November 2006 (UTC)[reply]
You'd be better off avoiding germanium and other 'rare earth' elements. Silica one of the most common elements in the Earth. Silica is no more inherently evil than any other thing. It's a thing. It can't be good or evil of itself - it's like a gun or a pen or the air your breathe. Franlkly, it's not to God if we are enslaved on Earth or not - it's all a part of having free will in the face of God's omniscience and omnipotence. If you believe he knows all and sees all BUT that he wants you to have free will then he lets man do unto man. If he thinks he has all of this and he DOES care about what we do to each other and intervenes, then you have no free will and what will happen will happen. QED it makes no difference in this world in respect to god.
Germanium is not a lanthanide. Silica is not an element, unless you cound "earth" as an element in the ancient, philosophical sense. --128.115.27.10 23:55, 1 December 2006 (UTC)[reply]

Why does burning natural gas produce 40% less CO2 than burning coal? edit

Why does burning natural gas produce 40% less CO2 than burning coal? This info is stated in the "natural gas" article. --206.170.183.60 19:27, 28 November 2006 (UTC)[reply]

Well, Natural gas is mainly methane, that contains an atom of carbon and four atoms of hydrogen. Coal on the other hand is mainly just carbon, with a small amount of other stuff thrown in. When a molecule of methane burns the by-products are an molecule of carbon dioxide and two molecules of water, when coal burns the majority of the by-products is just carbon dioxide. Vespine 21:46, 28 November 2006 (UTC)[reply]


Ah, the energy in coal is stored in carbon-carbon bonds, not carbon-hydrogen bonds. I was forgetting the lack of hydrogen in coal. Thanks. I hadn't realized that natural gas was such a supremely better fuel in terms of greenhouse gas production.--206.170.183.60 22:44, 28 November 2006 (UTC)[reply]

boron edit

what year was it decoverd? who decoverd it? how many common isotopes are in it? is there any safty infomashion on it? any facts on this element?

Wikipedia is an encyclopedia. Type boron into the search box and click the Go button. You'll find an article with plenty of information on boron much faster than asking someone else to read the article and answer your questions. --Kainaw (talk) 19:52, 28 November 2006 (UTC)[reply]

Surface area of a lightbulb edit

I'm doing a presentation on Thursday about processor heat dissipation. I'd like to make the comparison to a standard lightbulb (60 or 100 watts). To do this, I need to know - what is the surface area of a standard light bulb? Raul654 20:50, 28 November 2006 (UTC)[reply]

Note - according to this, your ordinary house light bulb is type A-19.
If you take a piece of paper that's 20 by 10 cm, you can completely cover the bulb with some overlap. So, the area is less than 200 cm2. Perhaps say, 150 cm2? --HappyCamper 22:23, 28 November 2006 (UTC)[reply]
Measure your lightbulb diameter with a pair of calipers. Assume its a sphere. Area is (4 Pi R^2).--Light current 23:27, 28 November 2006 (UTC)[reply]
If you don't have any calipers handy, just wrap a measuring tape around it to get the circumference, then find the diameter by dividing by pi. StuRat 07:15, 29 November 2006 (UTC)[reply]
FYI: A recent edition of EE Times stated that processor heat dissipation is currently around 50W/cm² and on its way to 100W/cm². In other words, much much higher than the dissipation at the surface of a standard incandescent light bulb.
Atlant 12:51, 29 November 2006 (UTC)[reply]
Yes, that's the point I'm going to make in my talk. It was 50 around 2002. We might have already passed 100, in fact. By comparison, a 100 watt light bulb probably gets 0.5 watt/cm2. Raul654 18:54, 29 November 2006 (UTC)[reply]
Well, an 11 Watt Compact fluorescent lamp, the sort of bulb often known as an "energy saver", gets about 0.1 watt/cm2. Laïka 19:11, 29 November 2006 (UTC)[reply]
Why would you use the surface area of the glass as opposed to the surface area of the filament? If you extend the analysis to the glass of the bulb, wouldn't you also need to extend the analysis of the processor to heat sink? Tbeatty 04:41, 1 December 2006 (UTC)[reply]

Equations edit

A)need help to solve: Fe(s)+O2(g)->F2O3(s)

B)CH4(g)+O2(g)->CO2(g)+H2O(g)

For A) you need the same number of Fe and O on both sides. In order to do this, look at what you have got:
Left side - 1 Fe + 2 O
Right side - 2 Fe + 3 O
Lets start with the O. The lowest common multiple of 2 and 3 is 6. Therefore it would be a good starting place to make it so that there are 6 O on each side. Now you are left with: Fe + 3O2 -> 2Fe2O3
Now, do the same with the Fe. You now have 4 on the right and 1 on the left. Therefore the answer is: <Removed answer. Please don't give the answer to homework questions, just guidance on how to get there :-) Skittle 22:43, 28 November 2006 (UTC)>[reply]
For B) you have:
Left side - 1 C + 4 H + 2 O
Right side - 1 C + 3 O + 2 H
Try balancing the H. You now have: CH4 + O2 -> CO2 + 2H2O
You now have 2 O on the left side and 4 on the right. Balance it to give: <Answer removed per above Skittle 22:43, 28 November 2006 (UTC)> You're done! --80.229.152.246 22:09, 28 November 2006 (UTC)[reply]
Solve? Perhaps you mean balance? Just see if the numbers of atoms balance on both sides of the arrow. In other words, just try adding constants. Look at how others answered. Try this one yourself, C6H14 + O2 --> H2O + CO2. (Complete Combustion of Hexane). 74.102.89.241 01:20, 29 November 2006 (UTC)[reply]

Fv vs Fab (Antibodies) edit

What's the difference between Fv and Fab with regard to antibodies? --Username132 (talk) 22:19, 28 November 2006 (UTC)[reply]

IANAI but I think Fab is the antigen binding fragment of the antibody, while Fv is the variable domain (and therefore a fragment) of Fab. Both Fab and Fv are used in antigen binding experiments.Mmoneypenny 00:55, 29 November 2006 (UTC)[reply]

I have wild hunch. Our antibody article just might help. alteripse 02:16, 29 November 2006 (UTC)[reply]

what do you feed it on?--Light current 02:23, 29 November 2006 (UTC)[reply]
I, personally, have domesticated hunch and they make great pets.Mmoneypenny 05:52, 29 November 2006 (UTC)[reply]
Actually, the antibody article was the first place I tried.. then Google...then here. --Username132 (talk) 09:21, 29 November 2006 (UTC)[reply]
A nice little article here [[3]] explains the whole thing in more detail.Mmoneypenny 10:01, 29 November 2006 (UTC)[reply]

Stock System edit

How do you find the name of ions using the stock System? For example: Fe2+ 216.253.128.27 22:44, 28 November 2006 (UTC)nicholassayshi216.253.128.27 22:44, 28 November 2006 (UTC)[reply]

Stock nomenclature needs to have an article written about it, I'm embarrassed to note. Still, our style guide conveniently contains a short description: Wikipedia:Naming_conventions_(chemistry)#Use_of_Stock_nomenclature. TenOfAllTrades(talk) 23:14, 28 November 2006 (UTC)[reply]

annihilation of matter edit

why is it called annihilation of matter when Dalton's theory state that All matter is composed of extremely small particles called atoms, which cannot be subdivided, creted or destroyed. would that contradict each other. Dragonfire 734 22:54, 28 November 2006 (UTC)[reply]

Dalton's theory is chemically correct, but quantum and atomic theory has superseded it. Atoms CAN be destroyed by atomic reactions. See atom bomb if you need convincing. Technically, they aren't really destroyed as much as change state into energy. Vespine 23:04, 28 November 2006 (UTC)[reply]
Mostly 'cause Dalton hadn't ever heard of Albert Einstein. We now know that matter and energy are equivalent and can be interconverted according to the famous relation E=mc². However, for practical purposes in everyday life (and chemistry) Dalton's approximation is very nearly correct. It's only when you get into the realm of nuclear physics that you start getting appreciable amounts of mass converted into energy—up to about 1% of the mass in a hydrogen bomb, and all of the mass in the extreme case of a matter-antimatter annihilation. TenOfAllTrades(talk) 23:11, 28 November 2006 (UTC)[reply]

battery edit

How does electrolysis differ from what goes on inside a battery?

In the case of a lead acid battery, electrolosis DOES go on inside a battery. Vespine 00:05, 29 November 2006 (UTC)[reply]
No, it doesn't, not unless you hook it up to another power source and run current through it the wrong way. Electrolysis is the opposite of electric power generation in a galvanic cell (one module of an electric battery). Electrolysis converts electrical energy into chemical energy; a galvanic cell converts chemical energy into electrical energy. —Keenan Pepper 04:58, 29 November 2006 (UTC)[reply]
Yes, it does. Batteries do both. For example, during operation of a simple zinc/copper battery, the copper plate builds up larger as the copper salt is plated onto the electrode. But the zinc electrode at the same time is dissolving. Or in other words, the zinc electrode is producing electrical energy while the copper electrode is using it to produce electrolysis. (The difference between these two quantities of energy is what the external circuit receives.) --Wjbeaty 04:49, 30 November 2006 (UTC)[reply]

Finding a table with the charge of Ions edit

Hi there,

Im in a high school chemistry class and we are doing a lot of work with combining ions and compound and what not. Nothing too difficult really. I am looking for a very helpful resource. I noticed that somebody had this very useful table which contained many common ions and their charge and formula and it was small enough to fit on a notecard. Our chemistry teacher allows one notecard on tests sometimes and that is a very handy resource. Iv been searching for a while and decided to drop a line over here to see if anybody knows of a page or table such as this. Thank you in advance!

--Sir Sid

The article Polyatomic ion probably isn't what you had in mind, but its external links look promising. —Keenan Pepper 04:47, 29 November 2006 (UTC)[reply]

We get sheets with common ions on for GCSE exams. Try http://www.aqa.org.uk/qual/pdf/AQA-4421-W-SP-07.PDF The bottom of Page 88 has what you're looking for I think! --86.139.127.29 15:50, 29 November 2006 (UTC)[reply]