Question

What percent of a present amount of radioactive radium (226Ra) will remain after 1200 years? The half life of 226Ra is 1599 years.

Answer 1

Answer:

59.44%

Step-by-step explanation:

$M_{R} = \frac{M_{O} }{2^{n} }$

$n=\frac{t}{t\frac{1}{2} }$

Where $M_{R}$ = mass remaining

$M_{O}$ =original mass.

t= time

$t\frac{1}{2}$ =half life

$t\frac{1}{2}$ =1599,  t= 1200, $M_{O}$ =226,  $M_{R}$ =?

$n=\frac{1200}{1599}$

n= 0.750469

$M_{R} = \frac{226}{2^{ 0.750469} }$

$M_{R}$ =134.3367amu

percentage of mass remaining = $\frac{134.3367amu}{226amu}$ *100%

                                                   = 59.44%