This setup allows stirring to proceed without heating the solution. Add a clean stir bar (set stirrer to ~150 rpm) and maintain this stirring mixture at ~40 ☌ by clamping the reaction beaker about 6- 10 cm above the hotplate surface. This solution of K2C2O4 is slightly basic. To the washed Fe(C2O4)2H2O precipitate in the beaker, add 3.0 mL of 1.7 M potassium oxalate solution (K2C2O4). WARNING: The oxidation reaction is exothermic. Oxidizing Fe(II)-oxalate to Fe(III)-oxalate using hydrogen peroxide. Combine the supernatant into one waste beaker. Swirl the suspension, allow the solid to settle, and remove the supernatant using a disposable transfer pipet. Wash the precipitate using 3-4 mL of hot DI water (~80-90 C, do NOT use water from the water bath). Set aside the supernatant in a labeled waste beaker. Decant the supernatant using a disposable transfer pipet without disturbing the precipitate. By now the yellow precipitate in the reaction beaker will have settled. Turn off the hotplate and remove the water bath to allow the surface of the hot plate to cool for step 4. Remove the solution from the water bath, and use a clamp to hold the beaker at a ~45-60 angle while allowing the precipitate to settle. Stir the solution a few times during heating. Let the water bath gently boil for ~5 minutes to completely form Fe(C2O4)2H2O (a vigorous boil may splash water into your reaction mixture). Keep the clamp loose on your reaction beaker to prevent it from breaking as it heats. Submerge the bottom of your 50-mL beaker into the hot water bath from step 1 until your reaction solution is below the water line. At this point, the iron is in the Fe(II) oxidation state. Record the pH using pH paper, and if necessary adjust the solution to be strongly acidic using 6 M H2SO4. Add the oxalic acid to the beaker containing the Fe(NH4)2(SO4)2 solution. CAUTION: Oxalic acid and oxalate salts are poisons use gloves while working with these compounds and be sure to wash your hands afterward. In a small graduated cylinder, measure ~6 mL of 1 M oxalic acid. Before t 1, particles are arrange in an orderly manner and close to one another. After t 4, the particles are very far apart and randomly arrange.Forming the initial Fe(II)-oxalate complex. State one different in the arrangement of the particles of substance Y before t 1 and after t 4.The kinetic energy of particles at t 3 is higher than the kinetic energy of particles at t 1. Compare the kinetic energy of particles of substance Y at t 1 and t 3.Why stirring of substance Y is required throughout the whole experiment? So that heat is spread evenly throughout the substance.Use oil bath or sand bath instead of water bath. Suggest another method which can replace water bath in this experiment.Substance X can not be boiled by using water bath. Why can’t we use water bath to determine the boiling point of substance Y? The boiling point of water is 100☌, which means the maximum temperature that can be achieved by water is 100☌, which is lower than the boiling point of substance-X. Given that the boiling point of substance X is around 105☌.
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