If the half-life of C^14 is 5600 years, how much C^14 will remain in a 12 gram sample after 28,000 years?

Question

Please help me by showing some work if possible. thx =)

Answer 1

28,000 Divided by 5600 = 5 half lives.

12/2 = 6

6/2 =3

3/2 = 1.5

1.5/2 = 0.75

0.75/2 = 0.375 grams left at the end.

Answer 2

initial mass at time zero is: m(0) = 12

half-life is 5600 m(5600) = (1/2)(12) = 6

another half-life m(11200) = (1/2)(1/2)(12) = 3

(a) express as a function of time t

m(t) = (12) 2^(-t/5600)

(b) m(t) = (12) 2^(-28000/5600)

(1) m(t) = (12) 2^(-5.000)

(2) m(t) = 0.3750

Hope it helps.

W.

Answer 3

2,333

Answer 4

The exponent will be (28000/5600) to determine how many half lives it went through.

12(.5)^(28000/5600) equals .375 grams.

Good luck to you !

Answer 5

Show work? Hmmm....Pretty simple to do in your head. In 5600 yrs, 6 gms. 11,200 3grms, 16,800 1.5gms, 22,400 .75gms, 28,000 .3755555gms

Answer 6

divide it by 2 five times