Four research teams measured the half-life of a radioactive isotope, and what each team wrote in its team notebook is shown in the table below. Suppose a later and more reliable measurement gives 0.790 s for the half-life of the same isotope. Decide which of the earlier measurements was the most accurate, and which was the most precise. ? team what was written in the notebook most accurate measurement most precise measurement Example 局 x 5 A "0.83s ±0.02s" B "0.75s" C D "between 0.778s and 0.782s" "0.810s ±0.50%" show work. don't give Ai generated solution

Technetium-99 is prepared from 98Mo. Molybdenum-SS combines with a neutron to give molybdenum-99, an unstable isotope that emits a particle to yield an excited form of technetium-99, represented as 99Tc*. This excited nucleus relaxes to the ground state, represented as 99Tc, by emitting a ray. The ground state of 99Tc then emits a particle. Write the equations for each of these nuclear reactions.

Define the term half-life and illustrate it with an example.

What are the two principal differences between nuclear reactions and ordinary chemical changes?