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 15:00
Which theory was contradicted by experiments with the photoelectric effect? light spreads out after it passes through a small opening. as soon as light strikes metal, electrons will be ejected. visible light, regardless of color, will cause the ejection of electrons when striking metal. the kinetic energy of ejected electrons depends on the frequency of light that strikes the metal.
Answers: 2
Chemistry, 22.06.2019 22:00
Plz ill give u brainliest which of the following steps is not likely to take place during cellular respiration? a.oxygen combines with carbon of simple sugar. b. energy molecule transfers energy to cells. d. energy is used up.
Answers: 3
Chemistry, 23.06.2019 01:00
An unsaturated hydrocarbon is a hydrogen-carbon compound with a. a network solid structure b. single bonds c. single bonds in a branched-chain structure d. double or triple bonds
Answers: 1
A gaseous mixture containing 1.5 mol of Ar and 3.5 mol of CO2 has a total pressure of 7.0 atm . What...
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