Asample of rock is found to contain 200 grams of a parent isotope. how many grams of the parent isotope will remain after one half-life?

Answer : The parent isotope remain after one half life will be, 100 grams.

Explanation : Given,

Initial mass of the isotope = 200 g

Time taken by the sample, t =

Formula used :

where,

= initial mass of isotope

N = mass of the parent isotope left after the time, (t)

= half life of the isotope

= rate constant

Now put all the given values in this formula, we get

Therefore, the parent isotope remain after one half life will be, 100 grams.

answer: land bridge theory. land bridge theory held that shifting portions of dry land explained the finding of identical species on different continents. plate tectonic theory eventually eliminated the land bridge theory.

this is more of a statement than a question. is there answers to go along with this, or is it opinion based?