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artcher [175]
3 years ago
9

Calculate the percent activity of the radioactive isotope iodine-131 remaining after 3 half-lives.

Chemistry
1 answer:
vovangra [49]3 years ago
3 0
Half life of a radio-active material is refereed to the time required for reducing its activity to 50 %.

Now, when I-131 passes 1st half life, it's activity will reduce to half i.e. 50%

When, I-131 passes 2nd half life, activity of I-131 will be reduced to 25%

On passing, 3rd half-life, percent activity of the I-131 <span>remaining will be 12.5 %.</span>
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Answer:

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Explanation:

<em>Which acid in each of the following pairs has the stronger conjugate base?</em>

According to Bronsted-Lowry acid-base theory, <em>the weaker an acid, the stronger its conjugate acid</em>. Especially for weak acids, pKa gives information about the strength of such acid. <em>The higher the pKa, the weaker the acid.</em>

<em />

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