A = (el)c Beer-Lambert Law (Eqn. 1a)

Y = mx + b (Eqn. 1b)

1. Use the color wheel and your knowledge of how light interacts with matter, to explain why your [Cu(NH₃)₄]²⁺_(aq) solution is blue.

2. You used graduated cylinders throughout this laboratory experiment to determine the percent copper in your mineral. Can you think of a way to increase the precision of your results?

3. Thinking about Eqn. 1a and mapping it onto Eqn. 1b, what does the slope of your line represent? To do this, write a mathematical expression for your line, remembering that you plotted A on the y-axis and c on the x-axis.

4. Using your mathematical expression for the slope of the line from question 3, calculate the molar extinction coefficient for [Cu(NH₃)₄]²⁺_(aq) at 620 nm. Show your work. Remember the cuvette has a 1 cm pathlength.