If the half life is 5 days, you would have to divide 222 by 2 3 times.
so 222/2 =111g
111/2 = 55.5g
55.5/2 = 27.75g
after four half life the mass would be
27.75/2
13.875g
the percent would be
13.875/222
= 6.25%
Answer:
the amount of valence electron, cna be found in the periodic table, which is called the atomic number which is top of the symbol
hope this helps!!! best fo luck to you
