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) β h2(g) + zncl(aq)the student collects the hydrogen produced over water at 25 Β°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 14:30
Ahypothesis must be testable and falsifiable to be considered scientific a. trueb. false
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Chemistry, 22.06.2019 18:00
Alidded glass container is filled with a colored gas. after a period of time, it is observed that the gas is uniformly spread throughout the box and that the movement has slowed considerably. next, a warm iron plate is carefully placed under the box. why is there resumed movement of the gas in the container?
Answers: 2
Chemistry, 22.06.2019 20:00
If one fission reaction of a uranium-235 atom produced two neutrons, how many neutrons would be released if the chain reaction occurred three more times?
Answers: 1
A bag containing a sugar solution is placed in a beaker of distilled water. The sugar cannot pass th...
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