Question

In the Unknown/Urea and Unknown/Cinnamic Acid mixtures only a LITTLE BIT of the Unknown was put in. Please identify the unknown based off this data and tell how you came to the conclusion.

8. Study the experimental melting point data in Table 2 for this experiment, with the goal of making a determination of the identity of the unknown (either cinnamic acid or urea) based on this data. Table 2. Melting Point Data # Compound/Mixture Observations/Comments Melting Point/C (mp) or Melting Point Range (rng)/C (mpr) Lit mp expt'l mp mg 134.3 to 136.5°C 1 cinnamic acid There was an experimental mp range instead of just one reading Lit mp 2 Urea expi'l mpr 131.2 to 134.3 °C 3 50/50 cinnamic acid/urea mixture cxpt'l mpr 983-C to 123.1 °C Looked like a small piece of solid remained at the surface of the liquid at 123.1'C. unknown (either pure cinnamic acid or expt'l mpr 134.1 to 136.2% pure urea) unknown/cinnamic acid mixture expt'l mpr 134.3 to 136.2 % 6 unknown/Urea mixture expt'l mpr 99.6 10 102.8°C What is the identity of the unknown? Cinnamic Acid 7 or Urea (circle or check the box) 9. Based on the melting point data in Table 2, determine the identity of the unknown (cinnamic acid or urea)? 10. Discuss and adequately justify your choice for the identity of the unknown in 8 based on the melting point data in Table 2.

Answer 1

Solution identity of unknown o cinnamic and because up of cinamic acid is 134.3 to 136.5c also unknown) cinnamic and mp is 134.3 to 136:20 which is very very accusate, Due to contamination, the mp Justification : cah sel of any decrease, we any solid where 50/50 3 in observation Urea mp is very cinamic and to their stand and value, low so taking Unknown the Jeference of obsearchion (3) when ( cinnamic acid) is mixed with urea (observthon 6) the mp decreases to ggo6 to 102.8°C 8o say that Urea is contaminated cinamic and hence, Unknown is cinnamic we can So by auid.