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Never handle sodium hydroxide pellets with your fingers. Use weighing paper and a scoopula. Solid sodium hydroxide will absorb water from the atmosphere. It is hygroscopic. Do not leave the container of sodium hydroxide open.

Keep ethanol and ethanol-water mixtures away from open flames.

Aqueous iron chloride will stain clothes permanently and is irritating to the skin. Avoid contact with this material.

 

In this experiment, you will saponify a vegetable oil

  • Pour 5 mL (5.0 g) of vegetable oil into a 250-mL beaker.
  • Slowly dissolve 2.5 g of NaOH pellets in 15 mL of the 50% ethanol/water mixture in a 50-mL beaker.
  • Add 2-3 mL of the NaOH solution to the beaker containing the oil. Heat the mixture over a hot plate with stirring. CAUTION: Keep your face away from the beaker and work at arm's length. Stirring is required to prevent spattering. Every few minutes, for the next 20 minutes, add portions of the ethanol/water mixture while continuing to stir to prevent spattering. After about 10 more minutes of heating and stirring, the oil should be dissolved and a homogenous solution should be obtained.
  • Add 25 mL of water to the hot solution. Using the hot grips, pour this solution into a 250 mL beaker containing 150 mL of saturated NaCl solution. Stir this mixture gently and permit it to cool for a few minutes.
  • Skim the soap layer off the top of the solution and place it in a 50-mL beaker.
  • Into a test tube, place a pea-sized lump of your soap. Place a similar amount of laundry detergent in a second tube and a similar amount of laundry detergent in a second tube and a similar amount of hand soap in a third tube. Add 10 mL of water to each tube. Stopper each tube and shake thoroughly.
  • Estimate the pH of the solution using wide-range indicator solution or wide-range test paper. Record the results. Pour the contents of the test tubes into the sink and rinse the tubes with water.

 

Pre-lab: introductory organic reactions

(total 25 points)

Hopefully here for the Pre-Lab

Name(Print then sign): ___________________________________________________

Lab Day: ___________________Section: ________TA__________________________

This assignment must be completed individually and turned in to your TA at the beginning of lab. You will not be allowed to begin the lab until you have completed this assignment.

For questions 1-4, draw the structural formulae of:

1) 2,2 - dimethylbutane

 

 

2) 3-ethyl-2,4-dimethylpentane

 

 

 

3) 2,3,4-trimethylhexane

 

 

4) 3-ethyl-2-methylheptane

 

 

For questions 5-8, give the names of

5) CH 3 CH 2 CH 2 CH 2 CH = CH 2 size 12{ ital "CH" rSub { size 8{3} } ital "CH" rSub { size 8{2} } ital "CH" rSub { size 8{2} } ital "CH" rSub { size 8{2} } ital "CH"= ital "CH" rSub { size 8{2} } } {}

 

 

6) CH 3 CH = C = CH 2 size 12{ ital "CH" rSub { size 8{3} } ital "CH"=C= ital "CH" rSub { size 8{2} } } {}

 

 

7) CH 3 CH = CHCH 3 size 12{ ital "CH" rSub { size 8{3} } ital "CH"= ital "CHCH" rSub { size 8{3} } } {}

 

 

8) ( CH 3 ) 2 C = CHCH 3 size 12{ \( ital "CH" rSub { size 8{3} } \) rSub { size 8{2} } C= ital "CHCH" rSub { size 8{3} } } {}

 

 

For questions 9-11, give the structural formulae for:

9) hex-3-ene

 

 

10) 3-methylhex-1-ene

 

 

11) 2,5- dimethylhex-2-ene

 

 

For questions 12-14, give the names of:

12)

13)

14)

For questions 15-19, give the stuctural formulae of:

15) trans-1,2-dibromoethene

 

 

16) trans-1-chloroprop-1-ene

 

 

17) cis- hex-2-ene

 

 

18) pent-1-yne

 

 

19) 3-methylbut-1-yne

 

 

For questions 20-25, name the following compounds:

20)

21)

 22)

23)

24)

25)

Report: organic reactions

Hopefully here for the Report Form

Note: In preparing this report you are free to use references and consult with others. However, you may not copy from other students’work (including your laboratory partner) or misrepresent your own data (see honor code).

Name(Print then sign): ___________________________________________________

Lab Day: ___________________Section: ________TA__________________________

 

Observations:

Synthesis of esters 

Reagents Product Observations
C 7 H 6 O 3 size 12{C rSub { size 8{7} } H rSub { size 8{6} } O rSub { size 8{3} } } {} (salicylic acid ) + CH 3 OH size 12{ ital "CH" rSub { size 8{3} } ital "OH"} {} (methyl alcohol)    
CH 3 CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 OH size 12{ ital "CH" rSub { size 8{3} } ital "CH" rSub { size 8{2} } ital "CH""" lSub { size 8{2} } ital "CH" rSub { size 8{2} } ital "CH" rSub { size 8{2} } ital "CH" rSub { size 8{2} } ital "CH" rSub { size 8{2} } ital "CH" rSub { size 8{2} } ital "OH"} {} (1 - octanol ) + CH 3 COOH size 12{+ ital "CH" rSub { size 8{3} } ital "COOH"} {} (glacial acetic acid)    
CH 3 CH 2 CH 2 CH 2 CH 2 OH size 12{ ital "CH" rSub { size 8{3} } ital "CH" rSub { size 8{2} } ital "CH""" lSub { size 8{2} } ital "CH" rSub { size 8{2} } ital "CH" rSub { size 8{2} } ital "OH"} {} (amyl alcohol) + CH 3 COOH size 12{+ ital "CH" rSub { size 8{3} } ital "COOH"} {} (glacial acetic acid)    
C 2 H 5 OH size 12{C rSub { size 8{2} } H rSub { size 8{5} } ital "OH"} {} (ethanol) + CH 3 COOH size 12{+ ital "CH" rSub { size 8{3} } ital "COOH"} {} (acetic acid)    

Oxidation of an alcohol with acidified potassium dichromate(vi) solution.

Remember to describe what happens and explain the color changes.

What conditions and techniques would favour the oxidation of ethanol to

a. ethanal rather than ethanoic acid.

b. ethanoic acid rather than ethanal?

Add 10 drops of dil. H 2 SO 4 size 12{H rSub { size 8{2} } ital "SO" rSub { size 8{4} } } {} to 5 drops of K 2 Cr 2 O 7 size 12{K rSub { size 8{2} } ital "Cr" rSub { size 8{2} } O rSub { size 8{7} } } {} to the following alcohols Observations: color/smellSmell cautiously! Observations: color/smell on warmingSmell cautiously!
Ethanol   
Methanol   
Propan-2-ol   

 

Oxidation of an alcohol with acidified potassium permanganate (vii) solution

Remember to describe what happens and explain the color changes.

What is your final product?

Add 10 drops of dil. H 2 SO 4 size 12{H rSub { size 8{2} } ital "SO" rSub { size 8{4} } } {} to 5 drops of KMnO 4 size 12{ ital "KMnO" rSub { size 8{4} } } {} to the following alcohols Observations: color/smellSmell cautiously! Observations: color/smell on warmingSmell cautiously!
Ethanol   
Methanol   
Propan-2-ol   

 

Saponification of a vegetable oil

Reagent pH from indicator paper
Your soap  
Laundry Detergent  
Hand Soap  

w from the File menu, and then double-click your template.

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Source:  OpenStax, Honors chemistry lab fall. OpenStax CNX. Nov 15, 2007 Download for free at http://cnx.org/content/col10456/1.16
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