REZA KHATAMI - Activity--Measuring Planck's Constant

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The table shows a series of standard additions of Cu(II)to acidified tap water samples measured by anodic stripping voltammetry at a platinum electrode. The unknown and all standard additions were made up to the same final volume. 1. Plot absorbance as a function of the concentration of Cu (II) standard. Determine the equation of the line and the X intercept. Find the concentration of Cu(II) in the water.

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im not sure how to do 1

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Any concerns about using electrochemical sensing? what are the benefits and the dangers?.

0.10 mM KMnO4 has an absorbance maximum of 0.26 at 525 nm in a 1.000-cm cell. Find the molar absorptivity and the concentration of a solution whose absorbance is 0.52 at 525 nm in the same cell. Watch your units. A. 2.6 M-¹ cm-¹, 0.20 mM B. 2,600 M-¹ cm-¹, 0.20 mM C. 2,600 M-¹ cm-1, 0.05 mm D. Not Enough Information

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calculate the [FESCN2+] using volumes of stock solutions. Presume that all of the SCN- ions react. Next, record the light absorbance values of each standard solution. Volume Volume Volume [FESCN2+] Absorbance Standard Fe(NO3)3 SCN- H2O sample (mL) (mL) (mL) 1 2.50 2.00 20.50 0.1811 2 2.50 1.50 21.00 0.3219 2.50 1.00 21.50 0.4981 4 2.50 0.50 22.00 0.6328 Stock [Fe(NO3)3] = 0.200 M, Stock [SCN-] = 0.0020 M. %3D

The table shows a series of standard additions of Cu(II)to acidified tap water samples measured by anodic stripping voltammetry at a platinum electrode. The unknown and all standard additions were made up to the same final volume. a. What chemical reaction occurs during the stripping stage of the analysis?b. Plot absorbance as a function of the concentration of Cu (II) standard. Determine the equation of the line and the X intercept. Find the concentration of Cu(II) in the water.

What is the purpose of waiting 1s after a voltage pulse before measuring current in sampled current voltammetry?

Please can you solve this question in chemistry quickly

The table shows a series of standard additions of Cu(II)to acidified water samples measured by anodic stripping voltammetry at a platinum electrode. The unknown and all standard additions were made up to the same final volume. 1. What chemical reaction occurs during the concentration stage of the analysis?2. What chemical reaction occurs during the stripping stage of the analysis?3. Plot absorbance as a function of the concentration of Cu (II) standard. Determine the equation of theline and the X intercept. Find the concentration of Cu(II) in the water.

1. Virtual Lab Question: A solution of 0.0040 M copper dithizone transmits 66 % of the light at a particular wavelength in a cell of 1.5 cm thickness. What is the absorbance? What is the molar absorptivity? What is the concentration of a copper dithizone solution that transmits 20 % under the same conditions?

Q1. A solution (0.005 M), has a transmittance percent equal to 13.3%. Calculate the transmittance percent for 0.05 M solution? 133 x10-7 None 8.76 x10-9 1.74x10-7 1.33 x10-7 0.876x10-9

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1. A 10.0 mL sample of a diluted solution has a transmittance of 25.1%. Determine the connection of this solution. 2. If the diluted solution was prepared from 3.0mL of a concentrated solution, what was the concentration of the concentrated solution?

NBS light

A solution in an absorption cell of path length 2.00 cm transmits 22.1 per cent of light of 372 nm incident upon it. If the concentration of the component is 0.100 mmol/L, what is the molar absorption coefficient at this wavelength?  Ans = ____ L mol-1 cm-1.

Question 7 As the cell thickness increases, the intensity of the transmitted light also increases. Is this True or false? True False

Question 10 Which of the following statements is false about single beam absorption instruments? A Test tube is used as sample holder B) Tungsten bulb is used as a source Photovoltaic cell as detector Beam splitter is used to get parallel beam

For the prelab today, all solutions were made using the procedure as outlined in your lab manual. When the absorbances of the solutions were measured, the following data were collected: Part 1 Part 2 Solution Absorbance Solution Absorbance 1 0.000 1 0.000 2 0.300 2 0.343 0.450 0.498 4 0.600 0.642 0.750 5 0.777 Use the data given above to calculate the average value of K for the equilibrium: Fe* (aq) + SCN' (aq) - Fe(SCN)2*(aq) Average K = 3. 4- 3.