can alpha particles go through paper but not 3 mm of aluminum?
340340
Alpha particles are relatively heavy and relatively highly charges, so typically, a piece of paper will stop them. It's beta minus particles that will penetrate a couple layers but even they are stopped in your dead skin layer.
146528
27=13 protons + 14 neutrons.  For aluminium always have 13 protons (the atomic numbers), otherwise will be another element.  Number of electrons, it is not anion just the alumnium in the metallic state will be the same as atomic number, in this case 13.
724861
For the first question, , I think C is the least correct.  Alpha and beta emissions are particles, not rays.  B is also suspect, because not all radioactive emiissions are both particulate and energy.\n\nFor your true/false question, the answer is FALSE.  An alpha emission reduces the atomic number by 2, and reduces the atomic weight by 4.
743124
It depends on how precise you need to be.\n\nIf you're looking for a rough estimate a micrometer or caliper would be fine, though they will always underestimate the thickness since the paper will distort under the pressure of the instrument.\n\nIf you can assume that your piece of paper is of uniform thickness (and you have many pieces) you can measure the stack and divide by the number of sheets.  If you only have one piece you can fold it into a stack, measure that thickness and divide by the number of folds.  \n\nIf this is only a hypothetical question or you have some money to spend there are laser micrometers that can measure the thickness of transparent or semi-opaque films down to a few microns.
700891
Well.......here goes. This experiment relies on the solvent solution being absorbed into the paper, and climbing upwards. This then allows the separation of the test material / substance, which follows the solvent solution. Most solvents will quickly evaporate when introduced to the air, so for more accurate results, and an overall truer picture, the container should be sealed.
365797
reason:it was observed that when lighter atoms (usually less than 20) are bombarded with alphaparticles,atoms get radioactive in nature.practically also we can compare this to a thin man and a stout man
422082
Alpha particle is nothing but Helium atom (2 He 4)\nSo alpha decay causes a decrease in 2 tomic numbers and 4 mass numbers \nexample:  U (92, 238)----> TH(90, 232) + 2Beta particles\n\nBeta particle is like electron: so u will see  atomic number increases by 1 and no change in mass number\n\nGamma ray is just energy emission\nIs it clear?
701256
Well since paper supposedly bursts into flame at that temperature, then yes.  Unless you have some kind of super fire proof bible.
882980
put the counter closer cos alpha raysonly travel a short distance...maybe that will work?... \n\nor get something that will alter with radiation... i think there a material that changes colour when hit with radiation....\n\nOOOOOOOOOrr... get something that emits a longer range radiation ray when the alpha partiles hit it...that way u can get a good approx of the count
4518
well, i am not positive, but i suspect that it's because of alpha decays.  most heavy radioactive elements like uranium and thorium decay into other more stable elements like lead, by the emission of an alpha particle.  an alpha particle is basically a helium nucleus - two protons and two neutrons.  the alpha nucleus picks up a few electrons from the environment when it's released and voila, you get elemental helium.
281802
It can only go through very thin films. Light is very high freq. X-rays are used to find small holes in welds since they go through small places well, but not metal. The fact that they conduct electricity means the magnetic part will induce a current, which creates another wave (reflection).  I have heard there is enough light passing through plywood, you can look through with an amplifier, starlight scope, night vision.
322877
Rutherford's Discovery of Alpha Scattering\nI. The French Start First\n\nIn 1900, the Curies and Becquerel were studying radioactivity (Rutherford was in Canada, having just recently moved to McGill University in Montreal. He will return to England, but not for several years.) and they had occasion to determine if the alpha rays traveled in a straight line. Becquerel carried out the work.\n\nHe took some polonium (discovered by Pierre and Marie Curie) and made it into a straight line source, not the usual pencil of rays. He then used this long, narrow beam of alpha rays to make a photograph of a wire. He found that the shadows had sharp edges, even when the alpha rays had gone through a thin film of aluminum.\n\nMarie Curie gave the interpretation of the experiment. She said that this showed that the alpha particles were not scattered, that is, able to be bent from their path. Alpha rays traveled in nice, straight lines ALL THE TIME.\n\nThey were wrong.\n\nWe jump to 1903 and Rutherford announces he has succeeded in bending alpha particles with a magnetic (and an electrical) field. Becquerel, using his different techniques, checks and confirms Rutherford's results.\n\nWhat Becquerel does is aim his radioactive source (radium, now as well as polonium) at a narrow slit with a photographic plate on the other side. Of course, with no magnetic field, he gets a nice, crisp image of the narrow slit, directly in line with the radium source.\n\nWhen he turned on the magnetic field, he got Rutherford's result, that is, the alpha particles bent in the magnetic field.\n\nPart b of the figure shows the offset of the image on the photographic plate. It is not lined up directly with the open slit, labeled Y.\n\nBecquerel also reversed the magentic field's direction during the exposure and got a double image.\n\nThe images were exactly the same distance from the center and the edges of the traces ALWAYS were sharp and crisp.\n\nUp to this point, there was zero evidence of alpha particle scattering.\n\nII. Now, the evidence starts to accumulate\n\nThe work described above was all done in the early part of 1903 and it was in June of 1903 that Becquerel made the first observation that led to alpha particle scattering.\n\nHe noticed, right at the end of his experiments, that the images from the doubled set (when he reversed the magnetic field during the experiment) moved closer together as he moved the photographic plate away from the slit (that is, increased the length b in the diagram above).\n\nIt seemed that the radius of curvature of the alpha particles path through the slit Y increased as b increased, thereby moving the two images closer together.\n\nNow, Becquerel knew this equation:\n\nRH = v (M/E)\n\nR = the radius of curvature, H = the magnetic field strength, v is the velocity, and E/M is the charge-to-mass ratio of the alpha particle. (I know, I know, this equation just came out of nowhere. You'll have to trust me on this one, since I don't know how to derive the equation either.)\n\nWhat Becquerel did is assume E is constant, so this left him with the unpleasant thought that either v or M had to increase. Since it is very had to visualize the alpha particle SPEEDING UP as it traveled from its source, Bequerel decided that M must increase, that the alpha particle picked up stray matter as it traveled along.\n\nHe could not have liked it, but there wasn't anything else he could think of. Since Rutherford was busy with other work, he did not take up any checking on Becquerel's results. However, one Rutherford result will have bearing on scattering. Rutherford found (in July 1905) that the alpha particle decreased in velocity, until at about 6,000 miles per second, it would not make its presence known by ionizing gases or darkening a photographic plate.\n\nIII. We're getting there\n\nThe importance of the slowing down of the alpha particle meant that R (the radius of the curvature in a magnetic field)
973408
Talk about how paper is made.
647158
no.  The most anti-matter they can produce at one time is incredibly small, only a few particles the size of electrons.
819769
Read Angels and Demons. Although the antimatter making technique is totally impractical, it just might be possible to store the stuff in a hand-grenade sized container. Magnetic suspension has already been done, although it would make a large hand grenade with current technology.\nhttp://www.levitron.com/\n\nA truly perfect vacuum really is impossible, but a near-perfect vacuum could be done. Just as long as you eliminate all the gas molecules floating around, you should be safe enough. http://www.physlink.com/Education/AskExperts/ae290.cfm
726521
You can get putty like ones from art shops that remove dark HB and pretty much destroy anything apart from the pressure on the paper. they need to be cleaned a lot but can be molded to an easy shape and are dabbed rather than rubbed which means less white flakes and little paper ripping.
754186
Lacking more detail - my suspicion is that the release of H2 will cause the amount of aluminium to be to high...\n\n-dh