Aportable gasoline-powered generator produces electrical energy from gasoline. if the generator were 100% efficient (that is, 100% of the energy from the fuel burned is converted to electrical energy), how much electrical energy in kwh would be generated from 5 gal of gasoline? the chemical potential energy in gasoline is 1.3 x 108 j/gal.

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.)