The radioisotope actinium-225 has a half-life of 10 days. i begin with 16 kg of this isotope, how much will remain after 40 days?

In a chemical reaction at equilibrium, the rate of the forward reaction the rate of the reverse reaction. if the rate of the forward reaction more products are formed.

Use this information to determine the number of calends electrons in the atoms. which of the following correctly compares the stability of the two atoms? a) both are unreactive b) both are highly reactive c) a is unreactive and d is reactive d) a is reactive and d is unreactive

If we compare and contrast electromagnetic waves with sound waves, all but one statement is true. that is a) sound waves require a medium to travel while electromagnetic waves do not. b) electromagnetic waves can travel through the vacuum of space while sound waves cannot. c) electromagnetic waves must have a medium in which to travel, but sound waves can travel anywhere. eliminate d) sound waves must bounce off of matter in order to travel while electromagnetic waves do not require matter to be present.