Ash remains from an ancient fire pit was discovered to have only 12.5% of the original Carbon-14 it once contained. If the half-life of Carbon-14 is 5,730 years,
how long ago was this pit used? Show or describe how you solved this. *


Which of the following did jj thompson discover about atoms? a)an atom has an internal structure. b) atoms are tiny indivisible particles. c)electrons orbit the nucleus of an atom. d) the nucleus of an atom contains protons and neutrons.

How many mmols of tris-hcl are there in 100 ml of a 100 mm tris-hcl buffer solution at ph 8.1? note that the 100 mm refers to the sum of tris and tris-hcl concentrations?

Which samples do the atoms have the least kinetic energy