Lab 3 MW

A standard iron solution was prepared by dissolving 0.0140 g of pure iron in acid then transferring to a 50.00 mL volumetric flask with orthophenanthroline as a complexing agent. At a wavelength of 540 nm, the absorbance of the standard was 0.214 in a 1.00 cm cuvette. A 0.128 g sample of an iron ore was crushed and digested in 5 mL of concentrated acid. The digested sample was then transferred to a 10.00 mL volumetric flask and diluted to the mark with water. A 1.00 mL aliquot of the sample was transferred to a 25.00 mL volumetric flask, and diluted to the mark with water. A portion of the diluted sample was then transferred to a 1.00 cm cuvette and measured at a wavelength of 540 nm. The resulting absorbance was 0.216. Determine the % w/w of Fe in the iron ore.

Predict which test tube (A, B, or C) will glow the longest. Briefly explain your reasoning.

Copper on the left and zinc on the right. Write a description of the macroscopic observations you may expect when testing this experimental design.

To determine copper in a metallic alloy, 1.245 g of an alloy sample is dissolved in a 1: 2 mixture of acid. nitric and sulfuric acid. The dissolved product is made up to 250 mL with water (solution A). In a cell that is 1 cm thick, performs the measurement at the wavelength of maximum absorbance of a solution with a concentration of 750 ppm of copper, giving an absorbance of 0.505. What will be the percentage by weight of copper in the alloy if solution A gives us a reading of 16.8% transmittance in it? cell at the same wavelength?

Determine the color and approximate wavelength absorbed most strongly by blue solution.

Determine the color and approximate wavelength absorbed most strongly by yellow solution.

In terms of the theory of color absorption, explain two ways that a solution can be blue.

The iron content of a large lump of ore is determined by taking a single small sample, dissolving it in acid, and titrating with ceric sulphate after reduction of Fe (III) to Fe (II). What are the possible source of random and systematic errors?

A sample of steel was dissolved and the manganese present was converted to MnO4– (aq). Water was then added to give a final solution volume of 100.00 mL. A sample of this solution was examined and was found to have an absorbance at 525 nm of 0.560 (pathlength = exactly 1 cm). What is the concentration of MnO4– in the solution? (The molar absorptivity is 3.62 × 103 L/(mol cm).)

1. What is the color of copper(II) sulfate solution? 2. How does absorbance vary with concentration of the copper (II) solution? 3. How do you determine the concentration of the unknown solution of copper(II) sulfate?

Determination of metals in soil by AAS Soil Mass of Soil ppm (mg/L) Concentration of Cu in soil Absorbance 1 1.0101g     0.6545 2 1.0064g     0.6203 3 1.0018g     0.5287 Show the calculation on how to calculate the ppm and the concentration of copper in the sample (soil). (The final volume is 200mL)

1

Why are metals resposbile for the production of colour upon heating

Suggest a reason why copper(II) compounds are often colored but copper(I) compounds are colorless.

2. Cite application of the acid-sulfate solution in plating different metals commonly used in industry.

Determine the color and approximate wavelength absorbed most strongly by red solution.

Part a and part b only

Describe the physical properties of metals?

Approximate percent potassium there should be in potassium tris(oxalato)aluminate(III).

(A) if both sentences are true, (B) if both sentences are false, (C) if the first sentence is true but the second is false, and (D) if the first sentence is false but the second is true. 1. In oxygen fixation, the alkaline-iodide-azide solution was used to acidify the solution. The brown hydrated precipitate that formed in the process of oxygen fixation was magnesium hydroxide. 2.Visual inspection is enough to determine if water is of appropriate quality. The standards for drinking water quality are typically set by governments or by international standards. 3.Deeper levels of water often do not reach 100% air saturation equilibrium because they are not shallow enough to be affected by the waves and photosynthesis at the surface. The dissolved oxygen content is an important index when considering its suitability for town supply. 4. The normality (N) of a solution is determined by multiplying the molarity of the solution by its volume. In the standardization of the sodium thiosulfate…

Investingate and report the uses of ferromagnetic oxides in magnetic recording tapes

cobalt(II) nitrate and sodium phosphate get same result