What kind of small objects composes much of the universe
a. atoms
b. dark matter
c. anti-matter
d. my dreams
e. monster energy

At 300 mm hg, a gas has a volume of 380 l, what is the volume at standard pressure

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.)

Sulfuric acid is a polyprotic acid. write balanced chemical equations for the sequence of reactions that sulfuric acid can undergo when it's dissolved in water.