Step 1. Graph the calibration curve relating absorbance at 520 nm to gallic acid concentration. Fit a line function to the measured data points applying regression analysis with r2 > 0.80 (refer Calculations in Experiment 1).

Step 2. Calculate concentration of free gallic acid (Cfree) in the tannin extract as under:

Cfree (mM) = A520 x e where, A520 is absorbance at 520 nm and e is extinction coefficient obtained from linear regression.

Step 3. Calculate concentration of total gallic acid in free and gallotannin forms in 0.2 ml of the sample (Cs):

However, original volume of tannin extract was 3.34 mL. Hence, total concentration (CT) should be:

Step 4. Calculate concentration of gallic acid in gallotannin forms (Cg form), subtracting free gallic acid found in tannin extract:

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Aromatherapy Ambiance

Aromatherapy Ambiance

Aromatherapy, a word often associated with calm, sweet smelling and relaxing surroundings. Made famous for its mostly relaxing indulgent  feature, using aromatherapy has also been known to be related to have medicinal qualities.

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