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Because aggressive bases like KOH damage the cuticle of the hair shaft, potassium hydroxide is used to chemically assist the removal of hair from animal hides. The hides are soaked for several hours in a solution of KOH and water to prepare them for the unhairing stage of the tanning process. This same effect is also used to weaken human hair ...
Here is a similar formula from the 67th edition of the CRC handbook. Note that the form of this formula as given is a fit to the Clausius–Clapeyron equation, which is a good theoretical starting point for calculating saturation vapor pressures: log 10 (P) = −(0.05223)a/T + b, where P is in mmHg, T is in kelvins, a = 38324, and b = 8.8017.
Potassium methoxide is a white to yellowish, hygroscopic, odorless crystalline powder which reacts violently with water forming potassium hydroxide and methanol. The aqueous solutions obtained are highly basic and have a corrosive effect. The substance is classified as an inflammable solid with a spontaneous ignition temperature of 70 °C. [6]
Sodium methoxide is prepared by treating methanol with sodium: 2 Na + 2 CH 3 OH → 2 CH 3 ONa + H 2. The reaction is so exothermic that ignition is possible. The resulting solution, which is colorless, is often used as a source of sodium methoxide, but the pure material can be isolated by evaporation followed by heating to remove residual methanol.
The hydroxyl value can be calculated using the following equation. Note that a chemical substance may also have a measurable acid value affecting the measured endpoint of the titration. The acid value ( AV ) of the substance, determined in a separate experiment, enters into this equation as a correction factor in the calculation of the hydroxyl ...
An aqueous solution is a solution in which the solvent is water. It is mostly shown in chemical equations by appending (aq) to the relevant chemical formula . For example, a solution of table salt , also known as sodium chloride (NaCl), in water would be represented as Na + (aq) + Cl − (aq) .
Pellets of soda lye (sodium hydroxide) Pellets of potash lye (potassium hydroxide)Lye is a hydroxide, either sodium hydroxide or potassium hydroxide.The word lye most accurately refers to sodium hydroxide (NaOH), [citation needed] but historically has been conflated to include other alkali materials, most notably potassium hydroxide (KOH).
Methanol for chemical use normally corresponds to Grade AA. In addition to water, typical impurities include acetone and ethanol (which are very difficult to separate by distillation). UV-vis spectroscopy is a convenient method for detecting aromatic impurities. Water content can be determined by the Karl-Fischer titration.