Some familiar products contain some of the same type of atoms. for instance, the chemical formula for baking soda is NaHCO, the chemical for table salt is NaCI. which choice best describes why these three products have some of the same types of atoms in common? A. the three products have very similar properties
B. there are only so many elements that exist on earth
c. most solids and liquids will absorb some oxygen(O) from the air
d. most of the products now on the market contain sodium (Na)

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.)