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 19:00
Which is the solubility product expression for caf2(s)?  [ca2+]/[f–]2  [ca2+][f2–]  [ca]+[f]2  [ca2+][f–]2
Answers: 3
Chemistry, 23.06.2019 02:00
Which best describes the present-day universe? opaque, expanding very slowly, stars produce heavy elements transparent, expanding at an accelerated rate, stars produce heavy elements opaque, expanding at an accelerated rate, stars produce only hydrogen and helium transparent, expanding very slowly, stars produce only hydrogen and helium
Answers: 1
Chemistry, 23.06.2019 04:31
Pls i will do pls imma diewhat forms white light? (4 points)a. combination of all wavelengths of ultraviolet light b. combination of all wavelengths of visible lightc. absorption of electromagnetic waves d. absorption of infrared rays
Answers: 2
How many moles are in 34.6 g of sulfur oxide (SO)?...
Mathematics, 30.09.2021 22:50
Spanish, 30.09.2021 22:50
Mathematics, 30.09.2021 22:50
Chemistry, 30.09.2021 22:50
Business, 30.09.2021 22:50
Business, 30.09.2021 22:50
Mathematics, 30.09.2021 23:00
Geography, 30.09.2021 23:00