g Wait another 10 seconds. Then remove a second drop of the mixture to add to the next drop of iodine. h Repeat step g until the iodine solution and the amylase/ buffer/ starch mixture remain orange. i You could prepare a control drop for comparison with the test drops. What should this contain?
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.
A flame test was then conducted and the identity of the cation was determined. To determine the anion, the anion had to be separated first from the cation in the unknown compound. To do this, 0.1 grams of the unknown compound and 0.5 grams of sodium carbonate had to be boiled in 5 mL of distilled water. Once the solution boiled for 10 minutes, the precipitate was centrifuged out and the anion solution was left. 0.1 M silver nitrate was added to the anion solution and a precipitate was formed.
10 drops of each solution was added to the appropriate centrifuge tube. 6 M NaOH was added drop wise to each solution until a precipitate was formed, or until 20 drops were added. Another 10 drops of 6 M NaOH were added to the solutions that formed a precipitate. Again, 5 centrifuge tubes were labeled for the same 5 cations and 10 drops of each solution were added to the appropriate centrifuge tube. The 15 M NH4OH was added drop wise until a color change occurred, or until 20 drops were added.
First, we had to calculate how many grams of copper (II) sulfate we needed to form 100 mL of a 0.200 M solution of copper (II) sulfate. We determined that we needed to use 4.994g of copper (II) sulfate to make the solution. We added distilled water to the 4.994g of copper (II) sulfate in a beaker until it reached 100 mL. Then we put the beaker on a hot plate and added a magnetic stirrer. We determined that the mass of zinc necessary to completely react with the copper (II) ions in the solution was 1.308g.
Repeated this several time to make sure all iron was collected. 7. Held magnet of 10cm square paper, and carefully removed the plastic and allowed the iron to fall onto the paper. Weighed and determined net mass of iron powder/fillings. 8.
Boil at least 10 minutes. 7. While the metal is still in the boiling water bath, measure the temperature of the boiling water carefully with a thermometer and record to tenths, one decimal place, in Data Table 2 8. After the metal has been heating 10 minutes, remove the metal from the boiling water bath using the string. Immediately transfer the metal into the calorimeter cup so that the water covers the metal.
B. Tollens Reagent. Prodedure: 1. Number 4 clean 10-cm test tubes 1,2,3, and 4. 2. Put 15 drops of dilute (6 M) sodium hydroxide (NaOH), into each test tube and allow them to stand for at least 1 minute.
Allow the crystals to dry for 1 week then, weigh it, take a MP, and calculate the % yield. * Assemble the apparatus for reflux using the diagram (see figure 1), place boiling chips or a stirring bar in the bottom of the flask. * Weigh 2grams of finely ground nutmeg and combine with 10ml of diethyl ether in a 50ml round bottom flask. * Place a heating mantle under the round bottom, turned on and the heat was slowly adjusted until the mixture starts to boil for 45minutes, then let cool to room temperature by sitting it on the lab bench. * Pour a little ether over the nutmeg residue on the filter paper so that any Diethyl ethanol traces clinging to it is washed down and mixed with the filtered liquid underneath.
Controlled The controlled variables of the experiment were: A. The volume and concentration of the Hydrochloric acid. B. The concentration of the Sodium Hydroxide. Equipment List * Boiling Tube * 10 cm3 1mol dm-3 Hydrochloric Acid (HCL) * 15 cm3 1mol dm-3 Sodium Hydroxide (NaOH) * pH and Temperature Probes * Data Logger * Measuring Cylinder ‘ * Boiling Tube * Teat Pipette Method * Add 10ml of Hydrochloric acid, measured in a measuring cylinder, into a boiling tube.