If we start with 1.000 g of strontium-90, 0.887 g will remain after 5.00 yr. This means that the half-life of strontium-90 is yr.

For ai it's atomic number is 13 and it's mass number is 27 how many neutrons does it have

In the 1800s, one of the statements in john dalton's atomic theory was that atoms are indivisible. later experimental evidence led to the discovery of subatomic particles such as neutrons, electrons, and protons. what happened to the indivisible atom part of dalton's atomic theory, and why?

Which common material is an example of a polymer? (25 pts) a. steel b. plastic c. petroleum d. rubbing alcohol