Gamma
ray
Ultra-
violet Infrared
Radio
H.
X-rays Visible
Microwave
Which electromagnetic wave transfers the most
energy?
infrared
microwaves
radio waves
X-rays
Frequency (Hz)
1015 1013
1021
1019
107
10"
109
107
Intro
Done

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.)