The half life of pa-234 is 6.75 hr. how much of a 50.0g sample of this isotope remains after 20.25 hr

The parent isotope remain after 20.25 hours  will be 6.25 grams.

Explanation:

Initial mass of the Pa-234 isotope = 50.0 g

Time taken by the sample, t = 20.25 hr

Formula used :

where,

= initial mass of isotope

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

= half life of the isotope  = 6.75 hr

= rate constant

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

Therefore, the parent isotope remain after 20.25 hours  will be 6.25 grams.

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