Dear

**Arkcon**;

**I don’t believe** that the “

**Error-Bars**” will be very helpful, because:

.. differences in light intensity by less than 1%.

- is not very linear to Absorptions, but Absorptions is “very” linear to Concentrations!

That means that the “’1.0 %’ -Error-Bars” will have a

**different size** over de whole Absorptions scale.

Dear

**1stPlace**;

As the

**second** Question asks:

Using the above data, calculate the minimal concentration .

- it is required to solve

**prior** the first Question, otherwise you will not have any Concentration result!

To solve the

**1.** Question you best “see” the Spectrometer as only a little special Indicator!

- - So, at how much mL’s your “Indicator” has changed its color?
- - And the remaining you can handle as a normal “
**…….**”-Titration: It’s Stoichiometry!

Then to solve the

**2.** Question you need the Mrs. “

**Beer and Lambert**”, because you will have to translate:

- - Your Concentration and corresp. Absorption you have read from the Graph into an of
**ε**_{total}! - - 1.0% Transmittance into its corresponding Absorption (
**A**_{1.0%}). - - Finally you can translate your
**A**_{1.0%} with the help of **ε**_{total} into a Concentration.

Mrs. “

**Beer and Lambert**” with Graphs, Formulas, and Explanations you can find on:

I hope this gives you enough help to start your both Solutions.

Good Luck!

ARGOS

^{++}**P.S.:** For Stoichiometry the following page may be of some help: "

Stoichiometry Problem”

.