We are asked to provide an equation for the transformation of 2-phenylethanoic acid to 2-phenylethanol. This type of a reaction is converting a carboxylic acid to an alcohol, which is classified as a reduction reaction since we are decreasing the number of bonds to oxygen in the molecule. In order to reduce a carbonyl to an alcohol, we need a source of hydride, H⁻. Reducing the carboxylic acid once will convert it to the aldehyde. However, we need to reduce the functional group all the way down to an alcohol, which is another reduction step after aldehyde formation. Therefore, the hydride source of choice is lithium aluminum hydride, LiAlH₄.
A reaction scheme is provided to show the reaction of the reduction of carboxylic acid to alcohol. The first step is addition of lithium aluminum hydride which does the reduction, and the second step is a work-up of acid which protonates the alcohol to get the final product.
Answer:
- <u>Yes,</u> <em>all titrations of a strong base with a strong acid have the same pH at the equivalence point.</em>
This <u>pH is 7.</u>
Explanation:
<em>Strong acids</em> and <em>strong bases</em> ionize completely in aqueous solutions. The ionization of strong acids produce hydronium ions, H₃O⁺, and the ionization of strong bases produce hydroxide ions, OH⁻.
Since the ionization of strong acids and bases progress until completion, there is not reverse reaction.
The definition of pH is pH = - log [H₃O⁺]. Acids have low pH (below 7, and greater than 0) and bases have high pH (above 7 and less than 14). Neutral solutions have pH = 7.
Acid-base titrations are a method to determine the concentration of an acid from the known concentration of a base, or the concentraion of a base from the known concentration of an acid.
The<em> equivalence point</em> of the titration is the point at which the the number of moles of hydronium ions and hydroxide ions are equal.
Then, at that point, the hydronium and hydroxide ions will be in the stoichiometric proportion to form a neutral solution, i.e. the pH of the solution wiill be 7.
Answer:
Thermal energy is taken from heat sink in higher temperature. A thermal power machine does mechanical energy using part of the heat.
Part of heat taken are given in cold reservoir in lower temperature
Explanation: