Erica1dfanidn
Answered

Find answers to your questions faster and easier with IDNLearn.com. Discover trustworthy solutions to your questions quickly and accurately with help from our dedicated community of experts.

The half-life of carbon-14 is 5,730 years. How many grams of parent material will remain from a 120-gram sample of carbon-14 after 2 half-lives?

90

60

30

15

Sagot :

Konrad509idn
[tex]t_{\frac{1}{2}}=5730\\ N_0=120\ g\\ t=2t_{\frac{1}{2}}=2\cdot5730=11460\\ N(t)=?\\\\ N(t)=N_0\left(\frac{1}{2}\right)^{\frac{t}{t_{\frac{1}{2}}}}\\ N(11460)=120\cdot\left(\frac{1}{2}\right)^{\frac{11460}{5730}}\\ N(11460)=120\cdot\left(\frac{1}{2}\right)^2\\ N(11460)=120\cdot\frac{1}{4}\\ N(11460)=30\ g[/tex]
AL2006idn
After one half-life . . . 1/2 of the total parent material

After another half-life . . . 1/2 of the half remains = 1/4 of the total original parent

If the original parent is 120 grams, then (1/4 x 20) = 30 grams remains
after 2 half-lives.  It makes no difference what the substance is, or
how long its half-life is.
We value your participation in this forum. Keep exploring, asking questions, and sharing your insights with the community. Together, we can find the best solutions. Thank you for visiting IDNLearn.com. We’re here to provide accurate and reliable answers, so visit us again soon.