chemistry
posted by susan
Fluorine20 has a halflife of 11.0 s. If a sample initially contains 49.0 μg of this isotope, how much remains after 66.0 s ?

Steve
66s is 6 halflives, so
49.0 * (1/2)^6 = 0.765 μg
Respond to this Question
Similar Questions

chemistry
How do you find the halflife of an element? 
chemistry
use the nuclear decay equation to find out how much a 7mg sample of iodine 128 remains after 116 minutes if the half life of this isotope is 25 minutes. 
chemistry
A radioactive sample contains 2.45g of an isotope wiht a half life of 3.8 days. How much of the isotope in grams remains after 11.4 days? 
math grade 12
2. An isotope of sodium has a halflife of 15 h. A sample of this isotope has a mass of 2 g. a. [2] Find the mass equation that remains after t hours. b. [1] Find the mass that remains after 5 hours, to the nearest hundredth. c. [2] … 
Chemistry
After 1.78 years, 1.990 g of a radioisotope remains from a sample that had an original mass of 2.000 g. Calculate the halflife of the isotope. 
Halflife
After two hours, 1/16 of the initial amount of a radioactive isotope remains undecayed. What is the halflife of the isotope? 
chemistry
A radioactive sample contains 2.45 g of an isotope with a halflife of 3.8 days. How much of the isotope in grams will remain after 11.4 days? 
chem
The halflife of the Nobelium isotope No^257 is about 23 seconds. 644 seconds (or 28 halflife periods) after the isotope was released there were 20 grams remaining. The number of grans of No^257 after h half life periods is M= 20 … 
chemistry
A radioactive isotope of radium (Ra226) has a halflive of 1620 years. How much of this isotope remains after three (3) halflives? 
Chemistry(please check my answer)
A radioactive isotope of radium (Ra226) has a halflive of 1620 years. How much of this isotope remains after three (3) halflives?