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Identification Of Selected Anions Lab Answers

Question: Qualitative analysis

Answer: The examination of a sample of inorganic material to identify the ions that are present

Question: In some cases a tentative identification of an anion can be made from the silver nitrate test

Answer:

Question: What is the identification of the silver nitrate test based on?

Answer: Color of the precipitate and on whether or not the precipitate is soluble in nitric acid

*usually more tests are needed to identify bc two or more anions may give similar results

Question: What can the silver nitrate test prove the presence of?

Answer: A halide ion (CL-, Br-, I-) bc the silver precipitates of the other 3 anions dissolve in nitric acid

Question: Organic solvent test

Answer:

Question: Formula (un-ionized) equation

Answer: NaCl (aq) + AgNO3(aq) —-> AgCl (s) +NaNO3 (aq)

-shows the formulas of the substances in the equation as they were normally written

Question: Total ionic equation

Answer: Na+(aq) + Cl-(aq) + Aq+(aq) + NO3-(aq)—-> AgCl(s) + Na+(aq) + NO3-(aq)

-shows the substances as they occur in a solution

-strong electrolytes, precipitates, and gases are written in their un-ionized or molecular form

Question: net ionic equation

Answer: Cl-(aq) + Ag+(aq) —->AgCl(s)

-includes only those substances or ions in equation 2 (total ionic equation) that have undergone a chemical change

-therefore Na+ and NO3- havent changed and dont appear in the net ionic equation

Question: what substances will you be putting in the test tubes

Answer: NaCl, NaBr, NaI, Na2SO4, Na3PO4, Na2CO3 and two unknowns (2mL)

Question: -dispose of solutions containing decane in the container marked…

-dispose of solutions containing silver, barium in…

Answer: -”waste organic solvents”

-”heavy metals waste” container