6. During the synthesis of a Grignard reagent in diethyl ethersolvent, bubbles are observed on the surface of the magnesium.Select the correct identity of the bubbles.
a. The bubbles are gaseous O2.
b. The bubbles are gaseous H2.
c. The bubbles are gaseous diethyl ether.
d. The bubbles are gaseous magnesium byproducts.
7. Prior to the synthesis of a Grignard reagent, the magnesiumthat is used in the reaction must be activated. Select the actionthat best describes this activation step.
a. exposing the magnesium to UV light to promote its electronsto an excited state
b. increasing the temperature to 150 °C to oxidize the surfacelayer of magnesium
c. soaking the magnesium in water to clean the surface layer
d. scraping or crushing the magnesium to expose fresh,unoxidized surface
8. A synthesis procedure calls for the trituration of the crudeproduct prior to recrystallization. Select the most likelyconsequence of failing to triturate the crude reaction product.
a. Less of the crude product will recrystallize from therecrystallization solvent.
b. Less of the crude product will dissolve into therecrystallization solvent.
c. The recrystallized product will contain less impurities thanit would if it had not been triturated.
d. The mass of the recrystallized product will be lower than itwould have been if it were triturated.
9. Select the term that describes the act of grinding a solidwith a stirring rod or spatula in the presence of a solvent.
a. salting out
b. centrifugation
c. sonication
d. trituration
10. Select the action that will NOT help increase the yield of aGrignard reagent.
a. dry the glassware in an oven prior to use
b. use only anhydrous ether as solvents
c. scrape or grind the Mg pieces prior to use
d. rinse the reaction glassware with acetone immediatelt priorto use
11. A reaction product mixture containing hydrocarbons indiethyl ether is washed with saturated aqueous sodium chloride(brine) solution in a separatory funnel. Select the most likelyreason for this step.
a. This step is to extract sodium chloride into the etherlayer.
b. This step is to remove water from the ether layer.
c. This step is to extract the ether into the aqueous layer.
d. This step is to extract the hydrocarbons into the aqueouslayer.
