CHEM 151. GOTTLIEB.
A sample of the fake element elementium-224 has a half-life of 21.99 hours.
CHEM 151. GOTTLIEB.
Calculate the decay constant (in hr ¹).
Give your answer in standard form without units and rounded to 4 decimal places.
CHEM 151. GOTTLIEB.



Answer :

To find the decay constant for elementium-224, we follow these steps:

1. Understand the relationship between half-life and decay constant:
The decay constant ([tex]\(k\)[/tex]) can be found using the equation:
[tex]\[ k = \frac{\ln(2)}{t_{\frac{1}{2}}} \][/tex]
Where:
- [tex]\(\ln(2)\)[/tex] is the natural logarithm of 2, which is approximately 0.693.
- [tex]\(t_{\frac{1}{2}}\)[/tex] is the half-life of the substance.

2. Given data:
The half-life ([tex]\(t_{\frac{1}{2}}\)[/tex]) of elementium-224 is 21.99 hours.

3. Substitute the values into the formula:
[tex]\[ k = \frac{\ln(2)}{21.99} \][/tex]

4. Calculate the decay constant:
First, calculate [tex]\(\ln(2)\)[/tex]:
[tex]\[ \ln(2) \approx 0.693 \][/tex]
Now substitute [tex]\(\ln(2)\)[/tex] and the half-life into the formula:
[tex]\[ k = \frac{0.693}{21.99} \][/tex]

5. Perform the division:
[tex]\[ k \approx 0.031526 \][/tex]

6. Round the result to 4 decimal places:
[tex]\[ k \approx 0.0315 \][/tex]

Therefore, the decay constant for elementium-224, rounded to four decimal places, is [tex]\(0.0315\)[/tex].