Question

Name: Experiment 10: ID of Unknown Carbonyl pre-lab (4 pts) Refer to the introduction and the attached data sheets on aldehyde/ketone compounds (boiling! point; derivative melting points; refractive index) to answer the following questions... (4 pts) A student was given two unknown carbonyl compounds to identify during his organic chemistry lab period. He performed the following procedures on both unknown samples: - semicarbazone derivative formation -2,4-dinitrophenylhydrazine derivative formation - boiling point determination (by distillation) - refractive index His results are summarized in the table below... Sample Semicarbazone melting point Unknown 1 200 °C Unknown 2 142 °C 2,4-Dinitrophenylhydrazine melting point 237 °C 154 °C Experimental boiling pt 204 °C 100 °C Refractive index 1.537 1.389 Identify each unknown.

Answer 1

Answer: by wane ww in the Comparing the experimental values with the values given data sheet it can be concluded that a Unknown sample I is acetophenone pe and Unknown Sample 2 is diethyl kelsne į The experimental values of unknown sample I and I given for acetophenone in the data sheet are compared in Table 1 Table 1 Boiling Melting Point (Melting Point of 2,4-dinitro- Refractive I Point Some of one phenyl hyd ranzone (ANPH) Index Unknown Sample Experimental values de 2040 C 2000 I 237°c 1.537 |Acessphenone (values from 202°c) 1996 239°c data sheet) 1.534 The experimental values of unknown sample 2 and the values given for die tyl ketine in the data sheet are compared in Table 2. Table a Boiling Melting Point (Melting Point of 2,4-dinitro. Refractive Point semicarbon zone phenyl hydrozone (DNPH) Index Unknown Sample 2 100°c | 142°C 154°c 1.389 Experimental values Diethyl ketone 102°c | 139°c I 156°c (Values from 1.392 I data sheet) This comparison of the values shows that unknown sample Is acetophenone and unknown sample 2 is diethyl ketone.