7. Blue dextran is a branched polymer formed by combining many different individual glucoses. If 10,000 daltons (amu) is the size cut-off for molecules being able to move through the dialysis tubing, then what is the minimum number of glucose residues (CHoO) in a blue dextran molecule? a. about 60 b. about 600 c. about 6,000 d. about 60,000 8, A positive Benedict's test indicates that a. a carboxylic acid is present b. either an alcohol group or an aldehyde group is present e. an alcobol group is present d. an aldehyde group is present 9. In solution, glucose exists mostly in its alpha and beta forms. Glucose gives a positive Benedict's test because CHJOH OH H OH H HO OH HO H OH H OH a. many alcohol groups are present b. the alpha and beta forms of glucose are aldehydes c. the ring in the alpha and beta form of glucose can open to form an aldehyde d. a carboxylic acid is present 10, A mixture of starch and iodine mixture turns blue because a. starch is blue b. iodine is blue c. starch is a chain of glucose molecules d. iodine interacts with coiled starch molecules e copper (II) ion is reduced to copper (D) ion