Think about how pressure relates to volume and how gas behavior would change in different volumes. which of the following will have the largest positive value for sº? a) 1 mole of helium gas at 1 atm pressure. b) 1 mole of helium gas at 2 atm pressure. c) 1 mole of helium gas at 5 atm pressure. d) 1 mole of helium gas at 0.5 atm pressure

What is the solubility of substance?

An observation that requires measurement is called quantitative observable or qualitative

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.)