Answer : The value of diffusion coefficient is, 
Explanation :
Formula used :

where,
D = diffusion coefficient = ?
= 
= 
R = gas constant = 8.314 J/mol.K
T = temperature = 
Now put all the given values in the above formula, we get:


Thus, the value of diffusion coefficient is, 
Answer: Nothing
Explanation:
Cobalt-60 emits γ radiation and is used in many applications including cancer treatment: There is no change in mass number or atomic number during the emission of a γ ray unless the γ emission accompanies one of the other modes of decay.
-They can conduct heat
-They can conduct electricity
-They are typically stronger than non metals
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