When carrying out the acid-base extractions in lab, you notice that you were asked (in the "Hints of Preparation") to extract with sodium bicarbonate only once while the procedure directs you to carry out the extraction with a 2nd amount of sodium bicarbonate. Why might the omission of the second extraction cause you to obtain less than 100% recovery of the substance you are extracting?
After drying the ether layer containing the biphenyl with calciumchloride pellets, you remove the ether from the drying agent into another tared test tube. Why would the percent recovery be lower ifyou do not wash the calcium chloride pellets with additional amounts of ether and add the additional ether portions to the taredtest tube?