Answers: 2
Chemistry, 22.06.2019 11:40, Wemaybewrong
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.)
Answers: 1
Chemistry, 22.06.2019 12:40, carebear60
Quiz1. which physical state of nitrogen has the highest entropy? a solid© b gasoc liquid
Answers: 1
Chemistry, 22.06.2019 13:00, jaylanmahone223
6. using 3 – 4 sentences explain (in your own words) why water expands when it freezes? 7. using your knowledge of colligative properties explain whether sodium chloride or calcium chloride would be a more effective substance to melt the ice on a slick sidewalk. use 3 – 4 sentences in your explanation.
Answers: 1
6) The solubility of a gas is 4.5 g/L at a pressure of 1.0 atm. At what pressure will there be 45 g...
Mathematics, 01.01.2020 10:31
Mathematics, 01.01.2020 10:31
Mathematics, 01.01.2020 10:31
Mathematics, 01.01.2020 10:31