Procedure: Work alone on all parts of the experiment (and report). - We will assume that one "squirt" is equal to 1mL (more precise measurements are not required). - Add the second reagent (with careful mixing) until the color change is complete. - "Evidence" means an observation (e.g., color, color ppt, bubbles) used to identify a product. If applicable, write a specific color (yellow, green, etc.). Inference is valid in a few cases. - "Formula" means the chemical formula of the product (an ion, compound, or element), Only chemicals identified in Expt 7 are possible products. 1. Add 3mL of deionized water to 1mL of potassium permanganate. In the HOOD, add sodium sulfide drop by drop until the permanganate color has just disappeared. The oxidation product is elemental sulfur (S). The color of the manganese product is Bro wu) The reduction product is (formula) Complete the equation and balance it by the half-reaction method: (is it acidic, basic, or neutral? i.e., which solutions were combined?) MnO4+S2 Dark Brown ept 2. Add 2mL of sulfuric acid to 1mL of potassium permanganate solution. mixing) until there is a complete change in color (i.e., no permanganate color remaining). The color change indicates that the manganese product is . (formula) The other reagent must therefore have been oxiditer (oxidizod or fodmula) Consider what test you might do to detect the iron product and tyy it. Complete the equation and balance it by the half-reaction method: MnO4+Fe2+ Add about 2mL of sulfuric acid to 1mL of potassium dichromate. Then add iron (Ii) sulfate (with mixing) until color change is complete. The oxidation product is (formula). The evidence is inference areen color The reduction product is Cr31 (formula). The evidence is Complete the equation and balance it by the half-reaction method: Cr2O2+Fe2+ Add about 3mL of sulfuric acid to 1mL of potassium dichromate. Then add sodium nitrite (with mixing) unti change is complete. Use Experiment 7 summary tables to help identify products. The oxidation product is (formula). The evidence is The reduction product is (formula). The evidence is Complete the equation and balance it by the half-reaction method: Cr2O72+NO2 Add 2mL of sodium hydroxide to 1mL of potassium permanganate. Then add aqueous iron (ii) sulfate with mixing until the permanganate color disappears. What color is the final mixture? So the manganese product is Was manganese oxidized or reduced? Redliced Was the iron (ii) oxidized or reduced? ied (issebl What should the iron product look like in basic solution? bark green (can you see it in this mixture?) What test might you do to verity the iron product? Try it. Complete the reaction with the appropriate products in basic solution and balance by the hali-reaction method: MnO4+Fe2 Irom waste Step 1: Combine 2mL of iron (ii) sulfate solution with 2mL of sodium hydroxide to make it basic. Complete and balance the double-displacement reaction that has just occurred (not a redox reaction): FeSO4(aq)+NaOH(aq)Fe(OH)2+NaSO2 The iron product of this double-displacement reaction is the reactant in the following redox reaction: Step 2: Now add hydrogen peroxide to this mixture to cause a color change (bubbles are not part of the main red reaction, and should therefore not be used as evidence for a product). The oxidation product is Fe (OH)3 (formula). The evidence is Red - Procth pp) The reduction product is (formula). The evidence is Complete the equation and balance it by the half-reaction method: Fe(OH)2(s)+H2O2(aq)
