Chem lab midterm

Purpose of pentane for Avogadro’s experiment

Used to dilute Oleic acid so that it can be measured later in the experiment

Purpose of piston oil for Avogadro’s experiment

Spreads out along the surface to the water on the dish so that when the lycopodium powder is dusted on the surface it will stay in place.

Purpose of lycopodium powder for Avogadro’s experiment

Creates a visible surface so that when the oleic acid is put onto the surface and spreads out the difference between the oleic acid and the lycopodium powder will allow us to trace the volume of the oleic acid.

Absorbance equation 

Absorbance = molar absorptivity * path length of radiation(wavelength)  * concentration

Elements in Neutralization Titrations

KHP was the standard in the 1st titration as it was measured, diluted and then titrated with NaOH to create NaKP and H2O. After vinegar was the new standard with the acetic acid in vinegar (CH3CO2H) reacting with NaOH to create NaCH3 CO2

Titration vocab

analyte (unknown concentration), titrant (known concentration), indicator (color-changing substance), endpoint (observed completion), equivalence point (theoretical completion)

Qexp and Qcrit

determines if an outlier should be excluded. Equation for Qexp is the outlier - nearest neighbor over highest value-lowest value. If Qexp > Qcrit then reject the outlier