Question

HURRY!!!!
Select the correct answer.
The unstable isotope nickel-59 can be used to date rocks that contain it. Nickel-59 decays into the more stable cobalt-59. The nickel isotope has a half-life of 76,000 years. Which statement about nickel-59 is true?
A.
After 76,000 years, all the nickel-59 in a rock decays into cobalt-59.
B.
Nickel-59 can only be used to date rocks that are younger than 76,000 years.
C.
All the nickel-59 stabilizes after it completes one half-life period of 76,000 years.
D.
The amounts of nickel-59 and cobalt-59 remain the same over a half-life period.
E.
The amounts of nickel-59 and cobalt-59 tell how long ago the rock cooled to closure temperature.

Answer 1

Answer:

The correct answer is D.

Explanation:

Half life of the isotope is the duration in which half amount of the isotope has been decayed and half of its original amount is till present.

$t_{1/2}=\frac{0.693}{k}$

Where:

$t_{1/2}$ = half life of the isotope

k = Decay constant

Half life of Nickel-59 is 76,000 years, which means that time taken by the original mass of an isotope to get reduced to its half of the original amount is 76,000 years.

This also means that amount of nickel-59 left  to be decayed is equal to the amount of nickel-59 decayed into cobalt-59.

Answer 2

Answer:

The correct answer is D

Explanation: