How long will it take for 99.9% of a 0.00310 mg sample of radioactive chromium-51 to decay? The half-life of chromium-51 is 27.80 days, so give your answer in days.
Enter a numeric answer only do not include units
2007-04-28 16:53:30 · 1 answers · asked by owaifkahlfkjh 2 in Science & Mathematics ➔ Chemistry
(0.5)^(t/27.80) = 0.001
t/27.80 = ln(0.001)/ln(0.5)
t = 27.80ln(0.001)/ln(0.5)
y = 277.05 days
days remaining
0 1
100.00 , 0.082633907
200.00 , 00.006828363
210.00 , 0.00532148
220.00 , 0.004147136
230.00 , 0.003231946
240.00 , 0.00251872
250.00 , 0.001962889
260.00 , 0.001529719
270.00 , 0.00119214
271.00 , 0.001162784
272.00 , 0.00113415
273.00 , 0.001106222
274.00 , 0.001078981
275.00 , 0.001052411
276.00 , 0.001026495
277.00 , 0.001001218
277.01 , 0.001000968
277.02 , 0.001000718
277.03 , 0.001000469
277.04 , 0.00100022
277.05 , 0.00099997
2007-04-28 17:25:01 · answer #1 · answered by Helmut 7 · 0⤊ 0⤋