Chlorofluorocarbons rise to the stratosphere and Multiple Choice interact with UV energy to produce free radicals that react with oxygen to create ozone. interact with UV energy to produce free radicals that destroy ozone. react directly with stratospheric ozone to destroy it. react with free radicals to remove carbon dioxide.

Which of these properties, used alone, would be least useful in identifying most minerals? a. color b. luster c. streak d. density

If a solution had a ph of 7 what is the solution

Modern pennies are composed of zinc coated with copper. a student determines the mass of a penny to be 2.482 g and then makes several scratches in the copper coaling (to expose the underlying zinc). the student puts the scratched penny in hydrochloric acid, where the following reaction occurs between the zinc and the hcl (the copper remains undissolved): zn(s) + 2 hcl(aq) → h2(g) + zncl(aq)the student collects the hydrogen produced over water at 25 °c. the collected gas occupies a volume of 0.899 l at a total pressure of 79 j mmhg. calculate the percent zinc (by mass) in the penny. (assume that all the zn in the penny dissolves.)