Technetium-99m is an ideal radioisotope for scanning organs because it has a half-life of 6.0 hr and is a pure gamma emitter. Suppose that 440 Mg were prepared in the technetium generator this morning. How many milligrams would remain after the following intervals?
1. one half life
2. two half life
2007-03-11 10:06:11 · 4 answers · asked by orange_crush_05 6 in Science & Mathematics ➔ Chemistry
This is easy. After one half-life, half of the material is left.
So...
1. 440 x (1/2) = 220 Mg
2. 440 x (1/2) x (1/2) = 110 Mg
2007-03-11 10:08:57 · answer #1 · answered by Anonymous · 1⤊ 0⤋
1. 440/2 = 220 mg
2. 220/2 = 110 mg
2007-03-11 17:10:36 · answer #2 · answered by Newbody 4 · 0⤊ 0⤋
Every half life the numbers get cut in half. So, with 1 half life it'd be 220, with 2 it'd be 110.
2007-03-11 17:10:23 · answer #3 · answered by Moral Orel 6 · 0⤊ 0⤋
Since [Tc] final = [Tc] initial * .5^(t/t1/2)
at one half life t/t1/2 is 6.0 hours/6.0 hours = 1
so [Tc] final = [Tc] initial * .5^1
or simply [Tc] final = [Tc] initial * .5
so [Tc] final = 440mg * .5 = 220 mg
at 2 half lifes t/t1/2 is 12 hours/ 6 hours = 2
so [Tc] final = [Tc] initial * .5^2
or simply [Tc] final = [Tc] initial * .25
so [Tc] final = 440mg * .25 = 110 mg
2007-03-11 17:23:41 · answer #4 · answered by opticalwaveguy 1 · 0⤊ 0⤋