A sample of a radioactive isotope initially contains 20 x 10^10 atoms. After 16 days, 5 x 10^10 atoms remain. what is the half-life of the isotope?

A)12 days
B)20 days
C)10 days
D)16 days
E)8 days

From the options provided for each element below, choose the properties that it may have based on its location in the periodic table fluorine (f): highly reactive nonmetal shiny a conductor

Scientists have developed an explanation of a phenomenon from several verified hypotheses. the explanation has been confirmed through numerous experimental tests.which option best describes this explanation? a. scientific lawb. research questionc. hypothesisd. scientific theory

Which of the following statements is true about energy quantization at the atomic level? electrons in the outermost orbits are the most stable. electrons in all the orbits around the nucleus have the same amount of energy. electrons in the orbit closest to the nucleus have the least amount of energy. electrons absorb or release the same amount of energy independent of the energy levels.