Radioactive isotope X has a half-life of 500,000 years. This isotope may be found in some types of volcanic rocks. A particular sample of volcanic rock taken from a layer that covered up some of the earliest known human-like footprints contains 0.125 mg of isotope X. The volcanic rock sample originally contained 8.00 mg of isotope X. How long ago were these footprints made. I need the equation. Thanks. please I am stuck on this question. PLEASE

The footprints were made years long ago.

Explanation:

Radioactive decay follows first order kinetics.

Half-life of isotope X= 500,000 years

The equation for first order kinetics is :

N = amount left after time t  = 0.125 mg

= initial amount  = 8.00 mg

= rate constant

t= time  

Putting the values we get:

The footprints were made years long ago.

the atomic number will stay the same no matter how many electrons it has, so it doesn’t decrease nor increase. it’ll only change with a different number of protons

a polar bond is formed when electrons are shared unevenly between atoms