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ConcepTest: Einsteinium Half-life

ConcepTest questions by David McConnell , David Steer , Walter Borowski, Jeffrey Dick, Annabelle Foos, Jeffrey Knott, Alvin Konigsberg, Michelle Malone, Heidi McGrew, Kathie Owens, and Stephen Van Horn


The isotope Einsteinium-253 has a half-life of 20 days. If you began an experiment with an 80-gram sample of Einsteinium-253, how much would remain after 60 days?

a. 60 grams
b. 40 grams
c. 20 grams
d. 10 grams

Student Responses:

No data yet. The correct response is d.

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References and Notes:



Resource Type

Activities:Classroom Activity:Short Activity:ConcepTests

Grade Level

College Lower (13-14):Introductory Level

Ready for Use

Ready to Use

Earth System Topics

Time/Earth History, Solid Earth:Earth Materials:Elements


Solid Earth:Geochemistry, Chemistry/Physics/Mathematics, Time/Earth History


Teach the Earth:Teaching Environments:Intro Geoscience, Teach the Earth:Course Topics:Geochemistry