Write the Henderson-Hasselbalch equation for a propanoic acid solution ( CH 3 CH 2 CO 2 H CH3CH2CO2H , p K a = 4.874 pKa=4.874 ) using the symbols HA HA and A − A− , and the given p K a pKa value for propanoic acid in the expression. ?

The answer & explanation for this question is given in the attachment below.

1. for the first question, we must find the mass of the anhydrous salt, mgso₄. the molar mass for mgso₄·7h₂o is 246.47 g/mol, while that of mgso₄ is 120.37 g/mol.7.834 g mgso₄·7h₂o * 1 mol mgso₄·7h₂o/246.47 g * 1 mol mgso₄/1 mol mgso₄·7h₂o * 20.37 g mgso₄/mol = 0.647 g mgso₄

2. mass of water = mass of sample - mass of anhydrous salemass of water = 7.834 - 0.647 = 7.19 gpercent water in hydrate = 7.19/7.834 * 100 = 91.74%