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PLS HELP ME WITH THIS IM GONNA CRY ITS SO HARD....

Arsenic‐74 is used to locate brain tumors. It has a half‐life of 17.5 days. 90 mg were used in a procedure. Write an equation that can be used to determine how much of the isotope is left after x number of half-lives.

User Susannah
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1 Answer

16 votes
16 votes

Let that be x

Use the general formula used for calculating half-life


\\ \rm\Rrightarrow A=A_o(0.5)^{(t)/(h)}

  • H is half-life,t is time
  • time given x

put values

The equation is


\\ \rm\Rrightarrow A=90(0.5)^(x/17.5)

User McRobert
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