Ester Synthesis

Summary

In this lab, the students were asked to combine substances of acids and alcohols and notice the differences of the smells. From this, the students learned how molecules can be changed into different molecules using chemistry. 

Students were given three test tubes, labeled I, E, and M. In test tube I, students placed in 10 drops of isopentyl alcohol, 10 drops of glacial acetic acid, and 1 drop of concentrated sulfuric acid. In test tube E, students placed in 10 drops of ethyl alcohol, 10 drops of glacial acetic acid, and 1 drop of concentrated sulfuric acid. And in test tube M, students measured in 0.15 g of salicylic acid, 12 drops of methyl alcohol, and 3 drops of concentrated sulfuric acid. The students were asked to record the smell of all the substances into a data table.  

Our test tubes reacting inside the hot water

Data Table

Analysis Questions

1) The odors of the three mixtures after heating are sweeter compared to before heating. Before the heating the test tube I smelled like EXPO markers, test tube E smelled like glue, and test tube M smelled like salty stale crackers. After heating, test tube I continues to smelled like EXPO markers, but less pungent. However, it is very possible my group and I made an experimental error of not letting the vial react in the warm water long enough because many other groups said their substance smelled like banana laffy taffy.Test tube E smelled like nail polish, and test tube M smelled like spear mint/ spearmint gum.  

Test tube 1: EXPO marker

Test tube 2: Nail polish remover

Test tube 3: Spear mint

           

2) Based on the smell of the mixtures after heating, the functional group of ester molecules must be present in the final molecules that were produced, because of the sweet scent to the substances. 

Esther Molecule:

    H H H O     H H 

     |   |   |    |       |   |

H-C-C-C-C-O-C-C-H

     |   |   |            |   |

    H H H         H H

3) The new compounds were easily identified for my partner and I because the new fragrances were very distinct. Our test tube I, as I stated before, had an experimental error so our fragrance did not come out correctly, and cannot be used in conclusions. For our second test tube, test tube E had a very obvious nail polish remover smell, and the scent was exactly like the actual thing. Test tube M also smelled exactly like spear mint, but less fresh than the actual thing. 

Challenge Question