Level 2 – Melting Point Analysis – Interpreting Results A student is in a chemistry lab and is conducting an experiment with the aid of a list of compounds to choose from, similar to what we did in our lab. A student is given a compound and must confirm its identity. They suspect it is benzoin based on its appearance, but must confirm it first. They go to the literature and note the expected melting point; then they begin to conduct a melting point experiment. The instruments and thermometer/sensor are calibrated correctly. They write in their notebook the following: “MP is higher than expected (+15oC compared to the ‘suspected compound’ literature value)” -and-“narrow range (1.1oC from start to finish)”  What do the results of this melting point experiment most likely indicate?

Level 1 – H-NMR How many signal environments would the following molecule show in its 1H-NMR spectrum? (assume 

Level 1 – Chromatography and TLCs – Terminology In lab we discussed various types of chromatography and we experimented with two. For our TLC experiment, we used standard conditions for the stationary and mobile phases. What would an example of a stationary phase if we used reverse phase TLC?

Level 1 – Predicting Splitting Patterns of H-NMR When considering isopentanol, predict the resonance signal characteristics associated with the hydroxyl’s hydrogen.

Level 3 – Recrystallization Chemistry – Estimating Minimum Volumes Salicylic acid has a solubility of 0.2 g per 50 mL of water at room temperature (20 °C), and a solubility of 6.7 g per 50 mL of water near boiling (95 °C). What is the minimum volume of water (in mL) required to dissolve 12.0 g of salicylic acid?Select the closest possible answer.

Level 1 – H-NMR How many signal envionrments would N,N-diethylamine show in its 1H-NMR spectrum?

Level 1 – Extractions, Stoichiometry, and Solution Chemistry – The Classic Carbonate Example  Balance the following acid/base extraction equation: __a_ NaHCO3 (aq)  + __b___ RCOOH (aq)   ↔ ___c__ RCOO- (aq) + ____d___ Na+ (aq)   +  ___e____ H2CO3 (aq)  ↔  __f____ CO2 (g) +  ____g___ H2O (l)   (Answer Pattern: a:b    c:d:e      f:g)

Level 2 Infrared Spectroscopy – Reading the Spectrum   Which of the following best fits this spectra signal?

Level 3 – Liquid Chromatography, the Larger Scale of TLC – Predicting Order of Eluents Four compounds were combined and added onto a silica gel column with a mobile phase of Dichloromethane (DCM). The compounds were: I: PropanolII: CyclohexeneIII: 3-amino-hexanoic acidIV: Acetic acid Predict the compounds elution order from first to elute to last to elute (ordered left to right below).

Level 3 – Extraction of Caffeine – Following the Separatory Scheme During the Extraction of Caffeine lab, where was the organic fatty acids from the carnauba wax expected to be isolated from our product during the separation?