SOLUTION: Suppose a radioactive isotope is such that five-sixths of the atoms in a sample decay after nine days. Find the half-life of this isotope. Round your answer to 2 decimal places.

Question 515381: Suppose a radioactive isotope is such that five-sixths of the atoms in a sample decay after nine days. Find the half-life of this isotope.
Round your answer to 2 decimal places.
______ days.
Answer by ankor@dixie-net.com(22740) (Show Source): You can put this solution on YOUR website!
Suppose a radioactive isotope is such that five-sixths of the atoms in a sample decay after nine days.
Find the half-life of this isotope.
:
the radioactive decay formula: A = Ao*2^(-t/h), where
A = Amt remaining after t time
Ao = Initial Amt
t = time
h = half-life of substance
:
Let initial amt = 1
1*2^(-9/h) =
Use natural logs
ln(2^(-9/h)) = ln(5/6)
The log equiv of exponents
*ln(2) = ln(5/6)
=
using a calc
= -.263
-.263h = -9
h =
h = 34.2 days, half-life of substance

RELATED QUESTIONS
suppose a radioactive isotope such that one-seventh of the atoms in a sample decay after... (answered by josgarithmetic)

suppose a radioactive isotope is such that one-ninth of atoms in a sample decay after... (answered by josgarithmetic)

The half life of a radioactive isotope is 394 days. A sample of this isotope is 10 grams. (answered by ewatrrr)

A particular radioactive isotope decays from 220 milligrams (mg) to 184.8 mg in 17 days.... (answered by josgarithmetic)

Use the exponential decay equation, where A is the amount of a radioactive material... (answered by ankor@dixie-net.com)

A mass of iodine-131 atoms decays in such a way that half decay every 8 days. What... (answered by vleith)

Radioactive Decay. The amount of radioactive material, in grams, present after t days is... (answered by josgarithmetic)

PLEASE HELP!! The radioactive isotope thorium 234 has a half-life of approximately 578... (answered by stanbon,Theo)

A certain radioactive isotope has a half-life of 15 days. If one is to make a table... (answered by josgarithmetic)