Consider that the half-life of Polonium-210 is 140 days.What approximate daily percentage of decay does Polonium-210 demonstrate?% (Round to two decimals.)(Hint: use the Rule of 70 backwards by dividing by the half-life period instead of the rate.) What percentage of the original amount of Polonium-210 would be left after 425 days of decay? % (Round to two decimals.)
the fraction left after d days is
0.5^(d/140)
So, after 1 day, that is 0.99506 for a daily decay rate of 0.494%
Now just plug in d=425
To determine the approximate daily percentage of decay demonstrated by Polonium-210, we can use the Rule of 70. The Rule of 70 states that to find the number of years it takes for a quantity to double or halve, you divide 70 by the growth or decay rate.
In this case, the half-life of Polonium-210 is 140 days. To find the daily percentage of decay, we divide 70 by 140:
70 / 140 = 0.5
So, the daily percentage of decay for Polonium-210 is approximately 0.5%.
To calculate the percentage of the original amount of Polonium-210 that would be left after 425 days of decay, we divide the number of days by the half-life:
425 days / 140 days = 3.04
Since each half-life represents a decrease of 50% in the quantity, we can calculate the remaining percentage as follows:
50% * 0.5^(3.04) = 14.4%
Therefore, after 425 days of decay, approximately 14.4% of the original amount of Polonium-210 would be left.