Date: 31 October, 2012
1. Trifluoracetic acid will be stronger because it contains fluorine substitutes which are more
electronegative than chlorine atoms. This causes a major difference between the electro-
negativities of the atoms which results in easy dissociation of hydrogen from the acid to bond
with water molecules and form hydronium ions.
2. pK ofAHCN = 9.4 pK Af HF= 3.17
Since HF is a stronger acid than HCN (which can be inferred from the pK ), HF wAll act as the
proton donor and HCN will act as a base and accept the protons from HF
Adding ① and ②
From the lewis structure of HCN, , It can be concluded that the extra proton
from Hydronium will attach to the lone pair of electron and establish a bond.
3. Acid-Base indicators are used to detect the equivalence points of a titration. They must be weak
acid/base themselves and