Answer:
59.44%
Step-by-step explanation:
[tex]M_{R} = \frac{M_{O} }{2^{n} }[/tex]
[tex]n=\frac{t}{t\frac{1}{2} }[/tex]
Where [tex]M_{R}[/tex] = mass remaining
[tex]M_{O}[/tex] =original mass.
t= time
[tex]t\frac{1}{2}[/tex] =half life
[tex]t\frac{1}{2}[/tex] =1599, t= 1200, [tex]M_{O}[/tex] =226, [tex]M_{R}[/tex] =?
[tex]n=\frac{1200}{1599}[/tex]
n= 0.750469
[tex]M_{R} = \frac{226}{2^{ 0.750469} }[/tex]
[tex]M_{R}[/tex] =134.3367amu
percentage of mass remaining = [tex]\frac{134.3367amu}{226amu}[/tex] *100%
= 59.44%
