Plz help for brainlieast answer
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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, 23.06.2019 00:30
Element j is 1s 2s 2p 3s . (i) how many unpaired electrons does j have? (ii) is j a good oxidizing agent or a reducing agent? (iii) state reason for the answer.
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Chemistry, 23.06.2019 01:00
Who examines and coordinates the cleanup of polluted sites?
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Chemistry, 23.06.2019 07:00
Write a hypothesis that answers the lesson question, βwhile observing a chemical reaction, how can you tell which reactant is limiting? β hypothesis: if a substance is the limiting reactant, then . . because . .
Answers: 1
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