lalamonique310 lalamonique310

02-01-2018
Chemistry

contestada

the half-life of Zn-71 is 2.4 minutes. if one had 100.0 grams at the beginning, how many grams would be left after 7.2 minutes has elapsed?

Respuesta :

JoannaBlackwelder JoannaBlackwelder

02-01-2018

7.2 minutes is exactly 3 half-lives (3*2.4 = 7.2). For each half-life, we divide the amount we have by 2.
1st half-life = 100.0/2 = 50.00 g
2nd half-life = 50.00/2 = 25.00 g
3rd half-life = 25.00/2 = 12.50 g
So we have 12.30 g after 7.2 minutes.

Answer Link

Otras preguntas

Based on this excerpt from Ernest Heminway's "In Another Country," what is the contextual meaning of the phrase "feeling sick"? "I am sorry," he said, and patt

Banks channel money from savers to borrowers to

The National Reclamation Act directly affected the management of which natural resource? a. water b. lumber c. coal d. oil

What view of China's place in the world is revealed in qianlong's letter

What term identifies a blank screen or animation that automatically displays on a computer monitor after a specified period of inactivity? a. Control panel b.

what is the name for the protective structure that forms around the embryo

The Central Intelligence Agency backed the Bay of Pigs invasion of Castro's Cuba. a. True b. False

If f(x) = -7x + 5x2 + 10, what does f(-2) equal?

Patents and copyrights are two forms of protection for a. physical property b. intellectual property c. imaginary property d. potential property

How to write three different improper fractions that equal4/23