EXP273

Lizzie Clark with Andrew Lang
 * [remove span tags JCB]**
 * Researchers **

To recrystallize cinnamic acid using pure ethanol.
 * Objective **

Trans-cinnamic acid (MSDS) 125 mL erlynmeyer flask Stopper for erlynmeyer flask Weigh Paper Electronic Balance Chemical Spatula Funnel Pipette 25 mL volumetric flask 25 mL pure ethanol (MSDS) Hot water bath Cool water bath Thermometer Gloves Safety Goggles Lab Coat Vacuum Hose Ring Stand and clamp Buchner funnel Rubber filter column Filter paper Side arm flask Plastic spatula
 * Materials **

1. Weigh empty volumetric flask (in grams). 2. Weigh volumetric flask with 25mL of pure ethanol (solvent) in it. 3. Pour the 25mL of solvent into an erlynmeyer flask and place stopper on the top to prevent evaporation of solvent. 4. Calculate and measure out the amount of trans-cinnamic acid (solute) needed for the intended concentration. 5. Add measured trans-cinnamic acid to erlynmeyer flask with pure ethanol. 6. Place erlynmeyer flask in hot water bath and swirl periodically. 7. Gradually increase the water bath's temperature until all solute has dissolved. 8. Record temperature that the solute finally dissolves at. 9. Place flask aside to cool at room temperature. Planning Sheet for 2.0M solution **[cannot access JCB]** Planning Sheet for 3.0M solution **[cannot access JCB]**
 * Procedure **


 * Results **


 * Log **

<span style="font-family: Arial,sans-serif;">3/27/12
<span style="font-family: Arial,sans-serif;">*Flask A= 2.0M solution, Flask B= 3.0M solution <span style="font-family: Arial,sans-serif;">*Room temperature at 21.5 C <span style="font-family: Arial,sans-serif;">9:31- Empty flask A weighed 78.174g. Empty Flask B weighed 78.640g. <span style="font-family: Arial,sans-serif;">9:34- Measured out 9.716g exactly of cinnamic acid and poured into erlynmeyer Flask A. Measured our 17.264g of cinnamic acid and poured into erlynmeyer Flask B. <span style="font-family: Arial,sans-serif;">9:50- Poured 25mL of pure ethanol into each flask and stoppered. <span style="font-family: Arial,sans-serif;">9:55- Placed both flasks into warm water bath at 61 C, stirring occasionally till solute completely dissolved. <span style="font-family: Arial,sans-serif;">9:59- Flask A completely dissolved. Bath temperature at 73 C. Placed aside to cool at room temperature. <span style="font-family: Arial,sans-serif;">10:03- Flask B completely dissolved. Bath temperature at 69 C. Placed aside to cool at room temperature.
 * [did any precipitate form? JCB]**