An important application of exponential functions is working with half-life of radioactive isotopes in chemistry. These isotopes emit particles and decay into stable forms, in doing so they lose mass over time. Half-life of an isotope is the time it takes for the amount to decay by half. For example, the half life of Bromine-85 is 3 minutes. This means if you start with 60g of Br-85, 3 minutes later 30g will remain. How much Br-85 will remain after 20 minutes?

Water ionizes by the equation h2o(l)⇌h+(aq)+oh−(aq) the extent of the reaction is small in pure water and dilute aqueous solutions. this reaction creates the following relationship between [h+] and [oh−]: kw=[h+][oh−] keep in mind that, like all equilibrium constants, the value of kw changes with temperature.

Hot air balloons float in the air because of the difference in density between cold and hot air. in this problem, you will estimate the minimum temperature the gas inside the balloon needs to be, for it to take off. to do this, use the following variables and make these assumptions: the combined weight of the pilot basket together with that of the balloon fabric and other equipment is w. the volume of the hot air inside the balloon when it is inflated is v. the absolute temperature of the hot air at the bottom of the balloon is th (where th> tc). the absolute temperature of the cold air outside the balloon is tc and its density is ďc. the balloon is open at the bottom, so that the pressure inside and outside the balloon is the same. as always, treat air as an ideal gas. use g for the magnitude of the acceleration due to gravity.

Which of the following ocean acidification? are the most likely side effects of a ph less than 7.0 in the ocean b. more metal salts altering the ocean chemistry c. dissolution of the shells of marine organisms d. both a & b e. all of the above.