Can someone help me with an answer guide for these 5 sample questions? Describe

Question

Can someone help me with an answer guide for these 5 sample questions? Describe the methodology of calibration curves and explain how it is used in this lab. Sample quiz/exam questions %T to be 52.6%, what is its absorbance? its absorbance at the same wavelength if 50-mL DI water is added to this solution. a KMnO4 solution has a % transmittance of 52.8%, what is its molarity concentration? 3. 1. A student is using a Spec-20 to analyze the concentration of a solution. If the student measures the 2. A 10-mL solution of CuCl2 gives an absorbance reading of 0.30 au at a specific wavelength. Predict 3. Permagnate ion (Mn04-) is purple in color. Assume its calibration curve is known and given below. If ion Qn04) is purple in color. Assumeits calibration curve is known and given below. If Absorbance = (251.7 L·mol-1) × (Fe Concentration) + 0.0972 It is common to dilute stock solution to a specific concentration when it is used. How many mL of 6.0 M H2SO4 solution will be needed to prepare 10-L.0.1 M H2SO4 solution? 4. 5. A sample of 0.300 mg pure chromium was added to excess hydrochloric acid to form a 10.0 mL aqueous solution of a chromium (II) salt, which has a violet hue. Exactly 1.00 mL of the resulting solution was analyzed using a spectrophotometer in a 1.00-cm cell at 575 nm, and the percent transmittancefor the solution was 62.5%. What is the extinction coefficient? Include proper unit for extinction coefficient.

Explanation / Answer

Answer for Question 1:

According to beers-lambert's law absorbance is inversly proportional to transmittance
so if the % transmittance is 52.6% then the absorbance is (100% - 52.6%) 47.4%

Answer for Question 2:

As you have added 50 ml of DI water the 10 ml sample of CuCl2 has been diluted 5 times hence the absorbance is 0.3/5 = 0.06 au.

Answer for Question 4:

0.16 L of 6M H2SO4 solution is needed to prepare 10 L of 0.1M H2SO4 solution

Applying

M1V1 = M2V2

M1 = 6 M H2SO4
V1 = x
M2 = 0.1 M H2SO4
V2 = 10 L

V1 = (M2 X V2) / M1

= (0.1 X 10) / 6 = 0.16 L

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