You suspect an unknown compound possesses a disubstituted alkene. Select all pieces of spectroscopic information that must be present if your hypothesis is correct. signals in the 13C NMR spectrum around 140 ppm
stretch in the IR spectrum at approximately 1650 cm-1
signals in the 13C NMR spectrum around 200 ppm
signals in the 1H NMR spectrum around 5.5 ppm
stretch in the IR spectrum at approximately 1700 cm-1
stretch in the IR spectrum at approximately 2200 cm-1
signals in the 1H NMR spectrum around 10.0 ppm
stretches in the IR spectrum immediately above 3000 cm-1
broad stretch in the IR spectrum at approximately 3500 cm-1

One way in which the useful metal copper is produced is by dissolving the mineral azurite, which contains copper(ii) carbonate, in concentrated sulfuric acid. the sulfuric acid reacts with the copper(ii) carbonate to produce a blue solution of copper(ii) sulfate. scrap iron is then added to this solution, and pure copper metal precipitates out because of the following chemical reaction: (s) (aq) (s) (aq) suppose an industrial quality-control chemist analyzes a sample from a copper processing plant in the following way. he adds powdered iron to a copper(ii) sulfate sample from the plant until no more copper will precipitate. he then washes, dries, and weighs the precipitate, and finds that it has a mass of .