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1. A group of students from the instrumental analysis laboratory of the course analyzed the sodium content in a serum sample using ICP-OES. They used 5 flasks with 25 mL of sample serum in each and added different amounts of a standard 2.640MNaCl solution to a total volume of 50 mL . Calculate: a. Equation for calibration b. Serum sodium concentration

A sample of rainwater was collected from four separate locations across theMetroplex. Each sample was measured once by two separate methods for the presence ofsulfate. Determine whether the two methods are equivalent with respect to giving thesame answer for [SO42-].

Table of chemicals and reagents with their physicochemical properties (name, molecular formula, molecular weight, pKa, melting point, boiling point, etc.) Write a short outline or a flow diagram of the procedure List and safety issues Read and understand the MSDS information for each chemical used in this practical Experimental procedure Please do not scratch the clear sides of the UV cuvettes as this will invalidate your results. Part 1: Preparation of a calibration curve A calibration curve should be constructed using at least five concentrations of the pure paracetamol standard supplied in the range 3-15 ug/mL as follows: Weigh about 150 mg of paracetamol accurately and transfer to a 200 mL volumetric flask. Add 50 mL of o.1 M NaOH and dilute to about 100 mL with deionised water (DI). Shake and make up to volume with DI water. Dilute 10 mL of the resulting solution to 100 mL (volumetric flask) with DI water (= stock solution). Prepare standard solutions containing 3, 6, 9, 12 and 15…

S.s.s.s.s.s.g.g.g.f

V. Error Analysis/Questions For the following questions explain what specific error in calculating your Ksp value would occur (i.e. would the Ksp be too HIGH or too LOW), compared to the situation in which no errors occur. When you answer the question, consider how the situation affects the calculation of Ksp. Each answer must have an explanation and type the answer, please. A. The buret was not conditioned (it still had water in it) when you add the HCl. Would the Ksp be too HIGH or too LOW? B. There was Ca(OH)2 solid (that was not filtered off) in your solution to be titrated. Would the Ksp be too HIGH or too LOW? C. You measured 24.00 mL of Ca(OH)2 solution instead of 25.00 mL. Would the Ksp be too HIGH or too LOW? D. The HCl concentration was actually lower than the reported molarity on the bottle. Would the Ksp be too HIGH or too LOW?

SHOW SOLUTION PROPRELY

Think about the situation where you are investigating the relationship of study time vs. exam grade.a. Which variable would be on the x-axis (and why)?b. Which variable would be on the y-axis (and why)?c. Would you expect the slope to be positive or negative (and Why)? 2) Contrast and compare interpolation with extrapolation. Which is “safer” to use and why?3) Look up how “the best fit straight line” is constructed. The term “Least squares” should be in your explanation.4) If I plot some data and end up with a r2 of (-) 0.99, is my plot useless? Explain.