Answers: 3
Chemistry, 22.06.2019 11:40
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 13:30
What produces wave a)sound b) heats c)transfer of energy d)vibrations
Answers: 2
Chemistry, 22.06.2019 16:30
Explain in detail of the four major scientific developments that spurred the formulation of the plate tectonics theory
Answers: 2
What are the defining characteristics of matter...
Mathematics, 11.02.2021 22:20
Social Studies, 11.02.2021 22:20
Business, 11.02.2021 22:20
Advanced Placement (AP), 11.02.2021 22:20
Mathematics, 11.02.2021 22:20
Mathematics, 11.02.2021 22:20
English, 11.02.2021 22:20
Mathematics, 11.02.2021 22:20
SAT, 11.02.2021 22:20