All of the above are correct answers
How? Well radiation can be used to improve everyday life. Nuclear energy can be used in medicine and as tools of treatment, especially for cancer, and trace the movement of atoms in biological systems.
Hope i got the answer correct....
Half life is the time taken by a radioactive isotope to decay by half its original mass.
The original mass is 200 g
Time taken is 60 hours
Final mass is 25 g
Therefore;
Final mass = Original mass × (1/2)^n; where n is the number of half lives.
25 = 200 (1/2)^n
1/8 = (1/2)^n
n = 3
Three half lives = 60 hours
1 half lives = 20 hours
Therefore; the half life of the radioactive nucleus is 20 hours
count each atom of the reactants and the products
