UV/Visible Spectrophotometry II - Quantitative Analysis 1. How many calibration curves, with how many points each, are to be constructed employing the least squares method? 2. What is their purpose? That is, how will you use them? 3. How will you prepare your unknown? Give specific steps. 4. Explain the difference between single and double-beam instruments. 5. Are single-beam UV/VIS instruments common today? What kinds of instruments employ them? 6. How will you actually determine the amount of the two materials in your unknown? 7. Could three four or more compounds be quantified in the above manner? How