Measurement shows that 3.6E-10% of atoms in a sample of radioactive isotope disintegrate in 1.7 yr. What is the half-life (in years) of the process?
The teacher gave me the answer at 3.3E11 yr
But I have no idea how to do this problem! Please help me !
2006-12-16 02:08:38 · 2 answers · asked by jnieves01 1 in Science & Mathematics ➔ Chemistry
N = No * e^(-L * t)
I'm writing Lambda as L
Lambda(L) is the inverse of half life.
N = no. of atoms of radioactive elements present at a CERTAIN INSTANT
No= no. of atoms of radioactive elements present initially
This is the basic equation.
Substitute from your given data and solve
2006-12-16 02:12:01 · answer #1 · answered by Som™ 6 · 0⤊ 0⤋
A simpler way than using the formula is -
1. Find the rate of radioactive decay i.e. how many nuclei/atoms degraded divided by the time this took.
2. You then half the original amiount (i.e. when time = 0) of nuclei/atoms. You now simply want to find how long it will take for this amount of atoms to degenerate which can be done using the rate. FOR EXAMPLE if the rate is 500 atoms per year and half the original amount of atoms is 1000, it will take 2 years 4 this half life to be reached.
Aplpy this to your figures :)
2006-12-16 02:31:34 · answer #2 · answered by Anonymous · 0⤊ 0⤋