The volume of a sample of hydrogen gas was decreased from 11.63 L to 4.92 L at constant temperature. If the final pressure exerted by the hydrogen gas sample was 7.20 atm, what pressure did the hydrogen gas exert before its volume was decreased

Write a brief passage describing a neutral atom of nitrogen-14 (n-14). describe the number of protons, neutrons, and electrons in the atom, where each type of particle is located, and how the terms atomic number, mass number, and atomic mass are related to the particles. use the periodic table to you. 14 protons and eletrons since its a neutral atom

Which statement is usually true about the relationship between activation energy and reaction rates? low activation energy barriers result in low rates. high activation energy barriers result in low rates. low activation energy barriers result in no reaction. high activation energy barriers result in no reaction.

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.)