[oCh3m_nub]

1. How many isomers are possible for an aromatic compound with the molecular formula C₇H₇Br?
a) 2
b) 3
c) 4
d) 5
my answers #1:B

2. Which alcohol will undergo dehydration and form only one product?
I. 1-pentanol   
II. 3-methyl-2-butanol
III. t-butyl alcohol
a) I and II only
b) II and III only
c) I and III only
d) I, II and III
my answer: #2: C

3. How many different secondary amides have the molecular formula C₃H₇NO?
a) 1
b) 2
c) 3
d) 4
my answer: #3: B

4. This molecule has ___ tetrahedral stereocenters.
     CH₃
      l
CH₃CClCH₂CH(CH₃)₂
a) 0
b) 1
c) 2
d) 3
my answer: #3: A

5. A 400-mg sample of testosterone was dissolved in 15.0 mL of ethanol and placed in a 10-cm polarimeter tube. The observed rotation was +2.91^o. What is the specific rotation of testosterone?
a) +0.174^o
b) +109^o
c) +7.28^o
d) -109^o
my answer #5:

6. Explain how methyl-beta-D-glycoside is produced from beta-D-glucose?

7. When an unidentified saccharide is mixed with Benedict's reagent, the resultant solution is blue. The saccharide could be?
a) lactose
b) fructose
c) sucrose
d) glucose
my answer: C

8. What is the minimum number of nucleotide bases in the gene for the beta-polypeptides of human hemoglobin (146 amino acid residues)?
a) 146
b) 438
c) 292
d) We can't assign a number unless we know how many different amino acids are represented.
my answer: #8:

9. Most enzymes in the human body?
a) act efficiently in the pH range for 1 to 13
b) contain cofactors to aid in catalysis
c) form covalent complexes with their substrates
d) function effectively at 37^oC
my answer: B or D

10. The cofactor that contains a thiol group is?
a) riboflavin
b) thiamine pyrophosphate
c) nicotinic acid
d) coenzyme A
my answer: #10: D

[Schrödinger]

Ok, since there a lot of questions, let me begin with #1.
The answer to that question is not 3. What were the isomers that you identified?

#2 : Correct

#3 : What is a secondary amide? How many carbon atoms is the nitrogen attached to?

#4 : Correct

When you post a question and your answer, it would be helpful if you also show us your working. That way, you will know where you went wrong. And trust me, people wouldn't want to read such a lengthy post

And answers to a couple of questions above can easily be googled for. All you have to do is search.

[cupid.callin]

#1. (C) 4 isomers ... benzyl bromide, o,m,p bromotoluene

#2. How you get 1 product out of I ... doesn't rearrangement occur in alcohol dehydration.

#3. (B) 2 isomers ... N-methyl ethanamide & N-ethyl methanamide

#4. (A)

#5. http://en.wikipedia.org/wiki/Specific_rotation

#7. Benedict solution identify reducing sugar or more precisely aldehyde (not aromatic) .. both glucose & lactose has free aldehysic group so it could be (A) (D).

snacks please ...

[AWK]

7) read
http://en.wikipedia.org/wiki/Benedict's_reagent
read
http://en.wikipedia.org/wiki/Genetic_code
9. temperature of human body is ~.
10. compare\ structures of:
http://en.wikipedia.org/wiki/Coenzyme_A and http://en.wikipedia.org/wiki/Thiamine

[Schrödinger]

#2. How you get 1 product out of I ... doesn't rearrangement occur in alcohol dehydration.

Yeah, I noticed it too. But looking at the choices given, I thought the question did not want the student to account for rearrangement

[cupid.callin]

Thats funny ... They are teaching him wrong thing just to make it easy!!!