Cations and Anions Tests

Testing for Cation and Anions OBJECTIVE Determine the presence of a cation or anion by a chemical substance pition Determine the cation and anion in an stranger settlement All salinity ascendants have both positive (Cations) and forbid (Anions) ions disbandd in it. In this experiment you volition observe chemical reactions to determine the presence of specific anions and cations. Compare your observations with the reactions of the fuckn solutions and the unknown solution to determine the ions present in the unknown solution. You will use a flame scrutiny for the cations, Na+, K+, and Ca+2 action qualitative outpourings for Ca+2, NH4+, Fe+3.Qualitative tests will be used to depict anions, Cl-, SO42-, PO43-, and CO32-. Expected results of the qualitative test and the reactions are included in your procedure. summons Obtain from the stock room a loyal unknown salt to be analyzed for the presence of both cation and anion. HC1, HNO3 are strong acids and NaOH is a strong bas e so be careful when using them. utilise the plastic pipettes on the center counter to dispense your unknown solution. Approx. 20 drops is equal to 1 mL, All abandon go in the waste jar labeled for your class. Bunsen Burner Safety. Make sure you are up to(p) to get a spark out of the striker consistently puzzle out the flatulence hassle valve counter clockwise completely. Adjust the burner barrel so your are able to see through the air inlet add together the rubber tubing and posture the rubber hose on the mishandle nozzle. Turn the gas jet 90 degrees. Open the gas needle valve until you hear the gas and light. If you are non successful in liberation the burner, turn the gas off and try again. Cation Tests Al. Flame Test dog 3 test tubes, Na+, K+ and Ca+2. Bring the test tubes to the stockroom window to get your woodwind splint soaked in each of the solution. You will also be given an unused wood splint to use for your unknown. Get your solid unknown as well. pe rvade the unused wood splint in water. Observe the change in flame color when the known solutions above are burned. K+ gives a very(prenominal) fleeting color change. Ca+2 gives a very similar flame color as Na+. Now that you know how discover how Na+, K+ and Ca+2, you will test your unknown. commute a small amount of solid unknown to a scoopula and footslog the wood splint that was soaking in water in the solid unknown and burn. By the stopping point of Part AI, you should be able to refrain the presence or absence of Na+ or K+ and perchance Ca+2. Chemical Tests A2 Because the flame test for Ca+2 is sometimes inconclusive, the oxalate test is performed. If no immediate precipitation (cloudiness) is observed, heat in a water bath for 5 minutes. Water bath is set up in the southwest hood. A3 Ammonium chloride, NH4Cl, reacts with sodium hydroxide, NaOH, to form ammonia, NH3 gas. The presence of the NH3 gas is confirmed using a moistened red litmus paper place on the mout h of the test tube. Ammonia gas is basic and will turn red litmus paper blue. A4 Fe+3, iron ion, react with potassium thiocyanate, KSCN, to form a blood red solution. By the end of Part A you should be able to identify your one cation. You moldiness do all Tests for the known solutions. Part BThis part of the experiment test for the presence of anions, Cl-, SO42-, PO43- and CO32-. Bl Chloride ion, Cl-, reacts with silver nitrate, AgNO3 to form a precipitate that does not dissolve in HNO3. B2 Sulfate ion, SO42-, reacts with barium chloride, BaCl2, to form a precipitate that does not dissolve in HNO3. B3. Phosphate ion, PO43-, reacts with ammonium molybdate solution, (NH4)2MoO4, in acidic solution to form a yellow precipitate. A yellow solution all is a negative result. B4 Carbonate ion, CO32-, reacts with HC1 to form CO2 gas that is observed as bubbles. Part C. Each island will have a consumer product to test.