Which would result in radioactive decay? Check all that apply.

a neutron-to-proton ratio of 1:1 in a small nucleus

a neutron-to-proton ratio of 1:2 in a large nucleus

a nucleus that contains 90 protons and 100 neutrons

a nucleus that contains 8 protons and 8 neutrons

any isotope of the element uranium, which has atomic number 92

any isotope of the element potassium, which has atomic number 19

One way in which the useful metal copper is produced is by dissolving the mineral azurite, which contains copper(ii) carbonate, in concentrated sulfuric acid. the sulfuric acid reacts with the copper(ii) carbonate to produce a blue solution of copper(ii) sulfate. scrap iron is then added to this solution, and pure copper metal precipitates out because of the following chemical reaction: (s) (aq) (s) (aq) suppose an industrial quality-control chemist analyzes a sample from a copper processing plant in the following way. he adds powdered iron to a copper(ii) sulfate sample from the plant until no more copper will precipitate. he then washes, dries, and weighs the precipitate, and finds that it has a mass of .