Wednesday

January 28, 2015

January 28, 2015

Posted by **Anonymous** on Saturday, November 5, 2011 at 6:18pm.

after 47.5 years?

after 1008 years?

- chemistry -
**DrBob222**, Saturday, November 5, 2011 at 6:42pmk = 0.693/t

_{1/2}

ln(No/N) = kt

Substitute into equation 1 and solve for k, the substitute into equation 2 and solve for N. No will be 18, 47.5, 1008 years.

- chemistry -
**Anonymous**, Saturday, November 5, 2011 at 7:48pm.....it's actually asking for the % left after so many years

- chemistry -
**DrBob222**, Saturday, November 5, 2011 at 8:02pmSo N = amount left.

% = (N/No)*100 = ?

**Answer this Question**

**Related Questions**

word problem - The half life of cesium-137 is 30 years. Suppose we have a 10-g ...

Chemistry - Which radioactive sample would contain the greatest remaining mass ...

calculus - The rate at which an amount of a radioactive substance decays is ...

chemistry - The half-life of stronitum-90 is 28 years. How many grams of this ...

calculus - Suppose strontium-90 decays at a rate of 2 percent per year. (a) ...

Math - Suppose strontium-90 decays at a rate of 2 percent per year. (a) Write ...

NEED HELP WITH CALC - Suppose strontium-90 decays at a rate of 2 percent per ...

science - the half life of tritium is 12.5 years. How much of a 1 g sample will ...

Calc - Radioactive radium () has a half-life of 1599 years. What percent of a ...

matg - Cobalt-60 has a half-life of about 5 years. How many grams of a 300 g ...