# An isotope of cesium (137) has a half-life of 30 years. if 1.0mg of cesium -137 disintegrates over a period of 90 years how many mg of cesium -137 would remain

This is for school i tought myself how to do one of these problems but now its harder well i think so and there is more questoins i have and i need this explained like how u got the answer

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Half of it goes away in the first 30 years, leaving 0.5mg. Half of that goes away in the second 30 years, leaving 0.25mg. Half of that goes away in the third 30 years, leaving 0.125mg after 90 years.

Posted on Feb 23, 2012

Hi,
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Posted on Jan 02, 2017

SOURCE: Actinium-226 has a half life

Hope it helps

Posted on May 12, 2011

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