Similar to Beryllium, Zinc and Chromium are amphoteric, but Iron and Magnesium are not amphoteric, meaning that they form insoluble precipitates in basic solutions like excess hydroxide. In this experiment, the unknown sample solution will be mixed with water to dissolve the ions that
The normality of the unknown base is calculated after the solution has reached the end point. The amount of substance being delivered is calculated in units of equivalents per litre using the formula: VaNa = VbNb Experimental In order to titrate the acid with the unknown base, a solution of the acid was prepared. 5.1722 (±10%)g of potassium hydrogen phthalate acid is obtained using a weighing boat and transferred into a volumetric flask containing 250mL of boiled distilled water. Volumetric flask was shaken several times in order to assist the powder to dissolve. Once dissolved, 24.9734 (± 0.0045)mL of acid was pipetted into an Erlenmeyer flask along with 25mL of cool (recently boiled) distilled water.
The Sulfuric acid is a catalyst for the reaction. This is the equation. C12H22O11 [pic]12 C + 11 H2O Experiment 1 /Procedure/Results and Observations In the first test, Dr. Light had filled a beaker with cold water and later two drops of phenolthalene, no effect had happened yet. Next, two pieces of Sodium were applied. Then, the sodium had started to move 360o around the beaker which had released a gas known as H2.
At 50C our results indicated a solubility of 89 g/100mL of H2O which was close to the known solubility of 80 g/100mL. Introduction: When a salt, such as potassium nitrate or sodium chloride, is placed in water a dissolving reaction will occur. At first, the positive and negative ions of the salt compound are only attracted to each other. In order for the salt to dissolve, these bonds must be broken so that the ions disassociate from each other. In the water molecules, hydrogen is slightly positive and oxygen slightly negative so they are attracted to ions of the opposite charge, known as dipole attraction.
Then the content of the chloride in the original salt is then calculated using stoichiometry (Chemistry Department, 2014). Theory: Gravimetric analysis is the measurement of mass, which by definition is categorized into four types however the use of one is only necessary in this experiment, which is precipitation (Gravimetric Analysis, 2012). Therefore the goal is to determine the original amount of ion. This is by isolating the ion in solution by a precipitation reaction, filtering and washing the precipitate free of pollutants, then the conversion of that precipitate to a product of the unknown sample given (Gravimetric Analysis, 2012).Therefore determining the quantitative of that substance by the precipitation reaction. The equation of the precipitate proceeds as follow if followed by the criteria given.
In Cycle 4, the clear liquid formed in Cycle 3 was decanted. Afterwards 10 mL of distilled water was added once again. 9.0 mL of 3 M H2SO4 was added drop wise into the solution until a color change occurs. Thereafter Cycle 5 began and another 5 mL of distilled water was added to the reaction in Cycle 4. The beaker was placed onto a magnetic stir plate so that the stir rod could stir the solution while 0.5 g of zinc was added.
ISOPENTYL ACETATE SYNTHESIS Post-Lab Submitted by Vivian M. Chan Teaching Fellow: Long Nguyen Calculations and Conclusion: In this lab, isopentyl acetate was synthesized by combining isopentyl alcohol and acetic acid. In this reaction, molecules were joined through the intermolecular elimination of water. A method of liquid extraction was used to wash the product with water, Sodium Bicarbonate and Sodium Chloride. Simple Distillation was used to retrieve a more pure product. The final crude product yield was 0.91g and the pure product yield was 0.36g.
After a few minutes the acid dissolved the capsule creating a black foam that then turned into a clear liquid again. Once the liquid was clear again, the clamp was closed and the beaker was weighed. The temperature of the water was also taken. This was then repeated again for Trial 2 with a new capsule. Specialized Chemical Techniques: The specialized technique used in this experiment was
Chose and Obtain Sulfate Solution will form aqueous compound as sulfate when combined with anything is aqueous · Is an anion 3. Chose and Obtain Nitrate Is an anion · Need another anion to test and see if order of reactivity is correct for each anion Solution will always form an aqueous compound according to Alchem Table 4. Chose and Obtain Copper Used by different lab partners whose data was observed Carrying Out The Reactions & Collecting Data How Why 5.Place 10ml of water in a test tube Done so aqueous solution may be made 6. Take magnesium nitrate and place 3 drops into test tube with water Done to have one part of the reaction 7. Repeat step 5 and 6 but replace magnesium with zinc Done so 2 metals can be tested at the same time 8.
The indicator Phenolphthalein was the substance used to signal when the titration reached the point at which the reactants are stoichiometrically equal as defined by the balance reaction equation. Phenolphthalein is a chemical compound with the formula C₂₀H₁₄O₄ and is often written as "HIn" or "phph" in shorthand notation. Often used in titrations, it turns colorless in acidic solutions and pink in basic solutions. Sodium hydroxide or Hydrochloric acid would not have been as effective or accurate because they would have reacted with the water vapor from the air. In this lab setup, graduated cylinders or beakers were not used.