Organic Chemistry Acid Base Extractions

Matt Jones

Chm 212

12/1/11

Acid/Base Extractions

The purpose of this experiment is to separate either the organic acid (carboxylic acid) or organic base (amine) from a mixture that includes inorganic impurities (salt). You will purify it by recrystallization. It will then be analyzed by recording the M.P. of the dry solid.

We had extract B with the starting weight of 0.506g and our lab table partners had extract B with the starting weight of 0.500g. The physical appearance of the starting material was large white crystals for us and our table partners. The physical appearance of the final product for us was dry white brittle flaky product and for our table partners it was yellowish white hardened product.

The final weight for our product was 0.103g and for our table partners it was 0.160g. The percent yield ((mass of actual yield/mass of theoretical yield)*100) for us it was (0.103g/.2024g)*100=51% and for our table partners it was (0.160g/0.20g)*100=80%.

M.P. Table

Benzoic acid | 122.38°C |

4-aminoacetophenone | 96-102°C |

Ethyl acetate | -83.6°C |

HCl | |

NaOH | 318°C° |

Our 1st trial | 120.2-122.3°C |

Our 2nd trial | 119.8-122.2°C |

Table partners 1st trial | 103.0-107.0°C |

Table partners 2nd trial | 103.0-107.0°C |

Our M.P. ranges | 120.0-122.3°C |

Our table mates M.P. ranges | 103.0-107.0°C |

We identified our extract B after adding 1M NaOH and going through recrystallization and then getting the melting points as Benzoic acid. We concluded that our purity level was very high with our M.P.’s range at 120.0-122.3°C and benzoic acid’s M.P. is 122.38°C. Identifying with the I.R. spectrum we used the benzene ring at 3072.31 cm^-1 and the OH range at 2675.53 cm^-1 and the O with the double bond at 1687.07 cm^-1 to get benzoic acid.

For our trial the percent yield came to be 51% and maybe due to mistakes was not very efficient extraction process for us. Our table partners got 80% extraction a much better result. I believe...