Pour all the filtrate and washings into a 250cm3 volumetric flask. Make up to 250cm3 with 1.0mol dm-3 sulphuric acid(VI) acid. Stopper the flask and invert several times to thoroughly mix the solution. 5. Fill the burette with 0.005mol dm-3 potassium manganate(VII) solution.
Nest one Styrofoam cup in another 11. Obtain an exact mass of tap water (45-50g) to serve as cold water 12. Put a magnetic stirrer in the bottom of the calorimeter 13. Secure temperature probe to a ring stand 14. Place temperature probe through hole in cardboard lid and position probe about 1cm above bottom of calorimeter 15.
After the effervescence, (15mL) of concentrated HCl was added drop wise to the solution. The mixture was then heated for 15 minutes in a boiling water bath. In two separate small beakers (20mL) of distilled water was placed in one and (20mL) of 6M HCl in the other. Both beakers were placed into an ice bath. After heating, the mixture was cooled to room temperature and filtered by vacuum filtration into a fritted funnel to yield a purple product.
In another flask 50-mL of ice water was deposited with three-drop phenolphthalein. Using a volumetric pipet 50-mL of the 1-bromopropane was added into the empty flask in the bath. By the same method 50-mL of potassium hydroxide was delivered to the same flask while swirling the contents and remaining in the water bath. A 10-mL aliquot was immediately removed from the mixture and added to the ice water containing the phenolphthalein. When the pipet was half emptied into the ice water a timer was started.
4. Record the pH measurements in your table. 5. Rinse the beaker thoroughly, and pour into it another 25ml of tap water, and add 0.1M NaOH drop by drop, recording the pH changes in exactly the same way as for the 0.1M HCl. 6.
Gracen Seiler April 7th, 2015 Section- 109 Investigating Stoichiometry with Sodium Salts of Carbonic Acid Introduction- This experiment is intended to help find a better understanding of chemical stoichiometry through titrations of NaHCO3 and NA2CO3 with HCl. A chemical reaction is a process that involves rearrangement of the molecular or ionic structure of a substance, as opposed to a change in physical form in a nuclear reaction. Titration is when a measured amount of solution of unknown volume is added to a known volume of a second solution until the reaction between them is complete. The objective of this experiment is reacting sodium bicarbonate (NaHCO3) and sodium carbonate (NaCO3) with hydrochloric acid (HCl) to produce sodium chloride (NaCl), water (H20) and carbon dioxide (CO2). -Use the titrations of the following chemical reactions: NaHCO3 + HCl (aq) NaCl (aq) + H2O (l) + CO2 (g) 2HCl (aq) + Na2CO3 (s) 2NaCl (aq) + H2O (l) + CO2 (g) Experimental procedure- Two Erlenmeyer flask must be labeled “unknown 1 and unknown 2”.
-We measured in each chemical and added water besides, HCl we added NaOH. Next, we measured the water temperature to begin with then added the substance to it to determine the finally temperature. We minus the initial and finally to decide if the reaction is exothermic and endothermic. 5. Describe the anticipated temperature change of a system in which an exothermic process is taking place.
Keep swirling the solution until a pink color is visible throughout from the phenolphthalein. 8) If over titration occurs ask the teacher for further instruction. 9) Write down the final volume in the NaOH buret 10) Subtract the final volume of NaOH from the initial volume. 11) Repeat this process at least twice more. Materials: * Buret (50mL) * Graduated Cylinder (10mL) * Beakers (250mL) * Buret stand * Erlenmeyer flask (125mL) * Safety goggles * Buret clamp * 0.10M HCl (aq) (25.0mL) * NaOH (aq) Vocab: * Standard Solution: a solution containing a precisely known concentration *
Wash and add Gram’s iodine (mordant) - 1 min. 4. Drain off iodine, add alcohol (decolorizer) -15 seconds 5. Wash and add Basic fuchsin or Safranin (secondary stain)- 1 min. 6.
Using a measuring cylinder, pour 20 cm3 of 0.01M saturated cobalt (II) chloride solution at 0℃ and pour about 100 cm3 of deionized water to a 250 cm3 beaker. 2. Stir the mixture using a magnetic stirrer-hotplate. 3. Using a dropper, add 5 drops of concentrated hydrochloric acid to the solution.