aminobenzoic acid in a sentence

Examples

1. "' 4-Aminobenzoic acid "'( also known as " para "-aminobenzoic acid or "'PABA "'because the number 4 carbon in the benzene ring is also known as the " para " position ) is an organic compound with the amino and a carboxyl groups.
2. "' 4-Aminobenzoic acid "'( also known as " para "-aminobenzoic acid or "'PABA "'because the number 4 carbon in the benzene ring is also known as the " para " position ) is an organic compound with the amino and a carboxyl groups.
3. On that last one, I can understand why you might prefer the first one, but because the " A " means " Esters of aminobenzoic acid " and " B " means " Amides ", I believe a numerical sort is far more useful than a alphabetical one.
4. Let's say I have an amino acid ( not a biological one-- say it's 4-aminobenzoic acid with two pKa's : 2.50 at the + 1 state and 4.87 in the + 0 state . . . let's say the concentration is 0.1M . How do I calculate what the pH of the solution will be?