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iren2701 [21]
3 years ago
6

Thallium-201 has a half-life 73 hours. If 4.0 mg of thallium-201 disintegrates over a period of 6.0 days and 2 hours, how many m

illigrams of thallium-201 will remain?
Chemistry
1 answer:
monitta3 years ago
8 0

Answer:

\huge\boxed{\sf 1.0 \ mg}

Explanation:

Half-life = 73 hours

Disintegration period = 6 days 2 hours = (6*24) hours + 2 hours

= 144 hours + 2 hours

= 146 hours

<h3>No. of Half lives = Disintegration period / Half-life</h3>

No. of Half lives = 146 hours / 73 hours

No. of Half lives = 2

Hence, there are 2 half lives passed in 6 days 2 hours.

<u>Amount of thallium-201 left after first half-life:</u>

= 4.0 mg / 2

= 2.0 mg

<u>Amount of thallium-201 left after second half-life:</u>

= 2.0 mg / 2

= 1.0 mg

Hence, the amount of thallium-201 left after 6.0 days and 2 hours is 1.0 mg.

\rule[225]{225}{2}

Hope this helped!

<h3>~AH1807</h3>
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