2 Consider 6 g of 210Po a What is the rate in disintigration

2. Consider 6 g of 210Po. (a) What is the rate in disintigrations per sec? (b) What is the energy of the alpha? (c) What is the power deposited?

Solution

(a)

the disintigration per second is,

A = N[0.693/T_1/2]

= [m/M][N_A][0.693/T_1/2]

= [6*10^-9 / 210][6.02X10²³][0.693/138.376 days*24 hr*3600 s]

= 9.97e+5 dis/s

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the alpha decay reaction for Po-210 is,

Po (210, 84) .....> Pb (206, 82) + alpha

[209.982873 673u] .....> [205.974465 278u] +[4.002263 u]

energy of the alpha:

E_alpha = [4.008408395 u-4.002263 u]][c^2][931.5 Mev/c^2]

= 5.724 MeV

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Power is,

P =E/t = 5.724 MeV/s