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Actually, I'm not sure it's two weeks... I haven't bothered to look at a calendar for a couple months now, so all I know about the date today (without looking at the one built in to the forum) is that it's Monday of the third week of June.
Aujourd'hui a ete une journee fort interessante... Mon amie n'etait pas la, ce qui n'etait pas vraiement bien. Elle jouait une piece de theatre. Apres, en maths, on a discute de tout et de n'importe quoi, ce qui m'a permis de faire presque tous mes devoirs.
Bonjour, hello.
Like ganesh said, welcome.
Right. Sorry if my knowledge of the subject is a little spotty, I learned what I know on my own; the chemistry class at school is REALLY basic (no pun intended).
On the subject of bases and acids, does anyone here (besides me) know what the strongest acid and the strongest base know are?
Then what is ozone?
About ozone: if you put some into a test tube, when it reaches room temperature, it will turn into O2 so violently that the test tube doesn't shatter, it just turn into a pile of glass dust.
I was going to explain the naming process for hydrocarbons, but realized that it's pretty complicated, being that I learned it my Organic Chemistry book.
To give you the bases, a hydrocarbon chain with only single bonds between the carbons is an alkane. Alkanes are name as follows: take the Greek number of carbon atoms in the string, followed by the suffix ane
If the molecule has one or more double bonds between carbons, then it is an alkene. You name the alkenes in the following manner: number the carbons starting from both ends. Use the number set for which the first atom of a double bond has the lower number. Now there are two ways to proceed: you can either write the Greek number of carbons, followed by a hyphen, the number that corresponds to the first atom of the first double bond, another hyphen, and the ene. The other method is slightly different; you put the number of the first atom, then the Greek number, then the suffix.
If the molecule has one or more triple bonds between the carbons,it is an alkyne. Proceed as above, using the suffix yne.
2H2O2 is two molecules of hydrogen peroxide. Another thing about H2O2 is that it decomposes into O2 and H2O. This is written as: 2H2O2-->O2 + 2H2O.
By the way, O2 is not an element; it's just the natural, and most stable, form of oxygen. It is the only molecule that contains only oxygen that is stable.
For those who don't know anything about the subject, I'll start pretty basically: all matter in the universe is composed of molecules, which are, in turn, composed of atoms, which are composed of electrons and nuclei (protons, neutrons).
A chemical compound is a molecule. DNA is one of the largest types of molecules known to humans, but there are undoubtedly even larger ones somewhere out there.
There are about 200 known elements, or types of atoms, each with a different number of electrons and protons. quite a few of these have isotopes. Each isotope corresponds to a certain number of neutrons in the nucleus, and they each have slightly different characteristics.
The chemical symbols for each of the know elements can be looked up in a periodic table. A chemical compound is usually denoted in the following way: take the symbol for one of the elements in the compound, followed by the number of atoms of that element present in one molecule of the compound, followed by the same thing for each of the other elements present.
Here are a few relatively common compounds:
O2: Oxygen gas, necessary for life.
H2O: Water, necessary for life.
O3: Ozone, highly unstable at room temperature, provides shielding against UV light.
N2: Nitrogen gas, the most present gas in Earth's atmosphere.
CO2: Carbon dioxide, present in the atmosphere, byproduct of the breathing process of all living things, as well as the burning of hydrocarbons.
CH4: Methane, lightest hydrocarbon, decays rapidly in oxygen.
Cl2: Chlorine, poisonous to most forms of life, used to "purify" water in pools.
F2: Fluorine, also poisonous to most forms of life, used in toothpaste.
HCl: Hydrochloric acid, main constituent of stomach acid, relatively powerful.
In a way, I suppose it is natural, but it still seems odd that the mind would think that you consciously and rationally decided to move.
It may have been said here already, but an ice age is period of stabilization for the environment. The one that's coming is coming because humans have destabilized everything.
Here's an interesting analogy: take a flywheel. Set it spinning VERY fast. Now place a 1-pound weight on it. Watch what happens: the weight makes the flywheel destabilize, then the weight gets launched off. After the weight is gone, the flywheel might spin a little off-balance for awhile, then it will go back to normal.
We humans are the weight that destabilizes the flywheel, or the environment.
How about this gas:
wikipedia wrote:According to the Intergovernmental Panel on Climate Change, SF6 is the most potent greenhouse gas that it has evaluated, with a global warming potential of 22,200 times that of CO2 over a 100 year period (for countries reporting their emissions to the UNFCCC, a GWP of 23,900 for SF6 is used as it was decreted at the third Conference of the Parties: GWP used in Kyoto protocol).[3] Its mixing ratio in the atmosphere is lower than that of CO2 (about 4 ppt in 1990 versus 365 ppm of carbon dioxide),[4] its contribution to global warming is accordingly low.
SF6 is extremely toxic, being a compound of sulfur and fluorine, both of which are highly toxic to most known forms of life.
Here's something else that's scary: look up the Kola Peninsula; there are hundreds of nuclear submarines sitting at the bottom of the ocean, more nuclear power plants on a 100km2 area than in the rest of the world, and a dozen nuclear ice-breakers and other nuclear-powered ships sitting in the port, IN THE WATER. Apparently, spending a week in the air there takes about a decade off your life.
As for me, I can say that, yes, I turn off the computer using the power strip, as well as the TV. All the bulbs in the house are Halogens. The heating has been off since March, so I can say that this house is relatively low on the energy-consumption scale.
Would you be meaning that the point of view of the observer has a higher concentration of matter that it normally would? That still doesn't make much sense, but it's at least plausible.
Well, that part isn't, but the fact that your mind thinks it realized what happened and then reacted consciously is somewhat odd, being that you reacted as a reflex, and then realized what happened.
Actually, The Code Book is sort of a history of cryptography, from ancient Egypt to the future, so I can't say that what I said is a summary.
One of the things about polarized light is this: if you have two Polaroid filters on top of each other, at a 45-degree angle between them, then approximately half of the photons which hit the assembly will get through to the other side. The others will be stopped by the second filter, which is at a 45-degree angle from their polarization.
Here's some thing to think about, but perhaps not too much: it has been demonstrated that if a person is, for example, poked (by surprise) with a needle, their conscious mind only registers activity after they jump. However, the mind perceives things differently: in you mind, you think, "I realized I got poked, so I jumped." The actual order of events is the opposite: you jump as a reflex, and then realize and rationalize what happened.
If you don't find this odd, then you probably won't find anything odd...
Another example of time going awry is the fact that, in some cases, information available in the present can affect the (relatively recent) past... I'm not sure exactly what the circumstances surrounding the discovery of this are, but I'm pretty sure it has been demonstrated.
You mean the point of view of the observer, right?
Here is (again) G:
G1=3^^^^3
G2=3^^...^^3 (G1 up-arrows)
...
G64=3^^...^^3 (G63 up-arrows)
Knowing this, you can say for certain that the number I posted just above is bigger than G.
Oops! I said I would mention some things that are physical yet infinite, but I forgot what I was going to say (yes, I did have some in mind when I started the topic).
Here's one that isn't really what I had in mind, but I thought I should say something: the time it takes a non-moving object to move one attometer (if you don't know what that is, see Euler Avenue>Number Giants).
The idea of quantum cryptography was told to me in a book, The Code Book, by Simon Singh.
Basically, the idea is based upon the fact that a single photon, polarized using either an X scheme (where /=1 and \=0) and a + scheme (where |=1 and -=0), if it is intercepted, the interceptor cannot know which scheme it is on, and therefore has their best odds if they use a random scheme to attempt to decrypt it. If they get it right, they have a 100% chance of getting the right number. If they use the wrong one, they have a 50/50 chance of getting the right one (an X-polarized photon has that chance of getting through a +-filter), and either way, the person on the receiving end can tell, through a non-revealing check with the other person, whether somebody has tries to get the information. This whole process is used just as a Diffie-Hellman-Merkle key exchange, allowing the two correspondents to exchange a key for a symmetric cypher safely.
If you want more info, I suggest you read the book in question; it has a lot of information.
I've got 1 week of actual class left over here. The "official" last day is July 7th, but that last week is basically just fun and games. As for the two weeks between next Friday and the beginning of the week of the 7th, the 9th-graders (troisiemes) are doing a big exam, so all the teachers are going to be very busy, so the rest of us get two extra weeks off.
Today was a really good day for me, in a lot of ways; I got some good scores, made a couple of new friends, and a few more personal things went well.
I guess there isn't much to say right now, but my next post might just be in French.
Here's another big number, obviously larger than G, because of the number of iterations and the sheer size of the first step alone:
x1=10^^^^^^^^^^10
x2=10^^^...^^^^^^x1 (x1 up-arrows)
...
x(x1)=10^^^...^^^^^^x(x1-1) (x1-1 up-arrows)
Here's sort of what I was talking about: a single dimension in space. In the case above, the dimension is, well, I guess that, like you said, unbounded. A dimension that has no boundaries or ends.
Of course, in mathematics, there are plenty of ways of proving that a number is infinite, but a spacial dimension is not like a number.
Like I said in my example, a dimension can be considered one of two things until it is found to be the latter one: unbounded, with no ends; or bounded, with the end just out of sight at the moment. You don't have any way of proving that the latter is not true, but if do find the end, then you know that it does have one, thus confirming one theory and disproving the other.
Any direction in space. A physical line.
For example, to "prove" that two lines are parallel, you supposedly extend them to infinite lengths, and if they never cross, they are parallel. If they're infinitely long, isn't there an infinitely large probability of them crossing? also, if they're infinitely long, there would be no end, but it could still be called a VERY long line, because you would not be able to find the end either way, until one day somebody finds the end of the VERY long line, thus proving that it is just that. If the end is not found, both possibilities remain.
I figured I'd bring this up, considering the number of threads that stray towards the question of infinity.
Infinite comes from the Latin finus, which means end. The prefix, in, reverses the meaning to be without end. Thus, something infinite is something that has no end, or boundaries.
How exactly can you prove that a line has no end? You cannot see the end if there is none. You can only practically prove that it isn't infinitely long, but you can't prove that it is. This would seem to suggest that nothing physical is infinite, and that makes sense to people who cannot grasp the concept of infinity. However, there are some things that are infinite yet still physical. If you know any, tell; if not, I will.