Select the correct answer. Why is it necessary to use models to study ſubmicroscopic objects such as atoms and molecules?
OA .
These objects do not exist in the real world.
OB. These objects are too far away to observe,
OC. These objects are too small to see.
These objects can only be described mathematically.
OD
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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.)