Half-Life

Half-Life Time required for ½ of any given mass of radioactive nuclei to decay Characteristic for each isotope Range from fractions of second to billions of years Not affected by the chemical or physical environment of nuclide

Half-Life Map 1 ½ ¼ 1/8 1/16 1/32 0 1 2 3 4 5  multiply by fraction 1 ½ ¼ 1/8 1/16 1/32 Fraction Remaining # of Elapsed Half-lives 0 1 2 3 4 5  multiply by fraction Minitial Mfinal or  multiply by denominator

No. of half-lives Number of half-lives = ____time elapsed__ length of 1 half-life Look up half-lifes in Table N