2007-07-14 03:25:27 · 6 answers · asked by Hermione 1 in Science & Mathematics ➔ Chemistry
Lead is the most stable heaviest nuclei...Infact most of the mewly discovered heavier radioactive materials end up into stable Lead(Pb). Alpha rays as we know are helium atoms with two lost electrons (He2+). This means they are postively charged ions (2+ charge). Since electrons are available outside the nucleus they can be easily attracted by the alpha particles without much effort. Any free electron available will turn alpha particles into stable Helium atom.
So alpha particles when released in air only travel a few inches before they turn into more stable atom. They can't travel much even in skin. Infact they can be easily stopped by a sheet of paper(In contrast to gama rays which are only electromagentic radiation and not charges particles.)
If u recall Rutherfords experiment....where alpha particles were thrown towards gold foil....u will come to know that some particles passed through while others bounced back.
Similarly if alpha particels are thrown towards Pb, the chances that they will pass through will also depend on the thickness of lead sheet. Infact since lead nuclei is heaviest..it also have strong positive replusion for postively charged particles. So probably the alpha particles will be reverted back. However some might pass through if they are not able to attract electrons from lead, which has lower probability because there are easily available electrons in the outermost orbit(6p2) of lead. So all in all lead will never allow alpha particles to pass through them.
2007-07-14 04:04:12 · answer #1 · answered by Beurself 2 · 0⤊ 0⤋
Gamma rays will penetrate lead a little bit, but after about a centimeter there isn't going to be very much light left. It is about the same as X-rays, so most people would say lead is opaque to gamma rays.
Alpha particles are not light, and alpha particles would not get through lead at all. Alpha particles can be stopped by just about anything. If your teacher agrees that lead is transparent to alpha rays they should be fired for the reasons that they should know
1. Alpha particles are not rays
2. Alpha particles get absorbed by anything
3. They should have done the calculations in college of how much light will be present at different depths of a metal.
2007-07-14 03:59:11 · answer #2 · answered by smilam 5 · 0⤊ 0⤋
Alpha particles can be stopped by a sheet of paper!
Lead has much more density, and will block it with a layer thinner than a sheet of paper. So, no, lead is not transparent to alpha particles.
2007-07-14 03:34:17 · answer #3 · answered by Vincent G 7 · 1⤊ 0⤋
Alpha rays are already stopped by aluminum foil. Lead has a very tightly packed atomic structure and blocks alpha rays (He ions).
2007-07-14 03:35:06 · answer #4 · answered by Anonymous · 0⤊ 0⤋
Lead is not trnsparent to any radiation since it has a high atomic number Z and is so effective in stopping with great efficiency all ionizing radiations
2007-07-14 04:25:48 · answer #5 · answered by maussy 7 · 0⤊ 0⤋
hmm.. i thot they used LEAD to block all kinds of radiation.. Ecspecially those ionizing ones.. not sure about alpha..
2007-07-14 03:33:56 · answer #6 · answered by scoobydoo 2 · 0⤊ 1⤋