The hypothesis states that the fraction of
radioactive nuclei after n half-lives is 0.5”.

in this expression, the value 0.5 represents

a) the fraction of nuclei still radioactive after any
half-life cycle.
b)the fraction of nuclei still radioactive at the
start of the experiment.
c)the amount of time it takes half of the
radioactive atoms to decay.
d)the number of half-life cycles.

10. translate each of the following chemical equations into a sentence. a. 2 zns(s) + 3 o2(g) -> 2 zno(s) + 2 so2(g) b. cah2(s) + 2 h2o(l) -> ca(oh)2 (aq) + 2 h2(g)

Which of the following compounds does not contain molecules? question 2 options: co2 h2 nacl h2o

Me i dont know what to do! the table compares the number of electrons in two unknown neutral atoms. comparison of electrons atom number of electrons a 10 d 11 use this information to determine the number of valence electrons in the atoms. which of the following correctly compares the stability of the two atoms? both are unreactive. both are highly reactive. a is unreactive and d is reactive. a is reactive and d is unreactive.