The alpha, α – particles possess following 10 properties:
1. Alpha, α – particle carries double the positive charge of proton, which is equal to the charge on the helium nucleus.
2. Mass of an alpha, α – particle is roughly four times that of hydrogen atom i.e. it is equal to the mass of the helium nucleus.
The above two properties establish that an alpha, α – particle is equivalent to helium nucleus (or a helium atom which has lost its two orbital electrons i.e. a doubly ionized helium atom).
3. Alpha, α – particles are deflected by electric and magnetic fields.
4. The velocity of alpha, α – particle ranges between 1.4 x 107 ms-1 to 2.1 x 107 ms-1 , depending upon the source emitting it.
5. Because of large mass, the penetrating power of α – particle is very small, it being 1/100 times that due to beta, β – rays and 1/10,000 times that due to γ – rays . α – particle can be easily stopped by an aluminium sheet, only 0.02 mm thick.
6. Because of large mass and large velocity, α – particle have large ionizing power. Each α – particle produces thousands of ions before being absorbed.
7. The range of alpha, α – particles in air (distance through which they can travel in air) depends upon the radioactive source producing it. At normal pressure in air, the range of α – particle varies from 3 to 8 cm.
8. Alpha, α – particles produces fluorescence in certain substances, like barium – plantinocyanide and zinc-sulphide.
9. Alpha, α – particles affected photographic plate slightly.
10. Alpha, α – particles are scattered while passing through thin metal foils. Most of the α – particles are scattered at small angles, but a few of them are scattered at an angle more than 900 also.
These are the 10 properties of α – particles, if you know more, please discuss.
Please answer the following question:
The penetrating power of α – particles is:
1. less than beta particles
2, less than gamma particles
3. both a) and b)
4. none of the above,
Please submit your answer in comment section.