The half life of the radium isotope Ra-226 is approximately 1,599 years. If the amount left after 1,000 years is 1.8 g, what is the amount after 2000 years? Round your answer to Three decimal places.
A)1.167 g
B)0.939 g
C)1.800 g
D)0.490 g
E)2.334 g

Question

Quizplus · Accepted Answer

The half-life formula is used to calculate the remaining amount of a substance after a certain time. Given the half-life of Ra-226 is 1,599 years, and after 1,000 years there's 1.8 g left, we can calculate the amount after another 1,000 years (totaling 2,000 years) by applying the formula again. Since 2,000 years is not a full half-life period, the calculation involves determining the fraction of the half-life that has passed and applying it to the initial amount. After 2,000 years, less than half of the 1.8 g would remain, and among the options given, 1.167 g is the correct calculation, considering the decay over the additional 1,000 years to total 2,000 years.

The Half Life of the Radium Isotope Ra-226 Is Approximately