Question

Pls draw the rough graph out, and show the calculation of Initial PH, PH at half-equivalence point and equivalence point!!! pls draw the graph out and how the number, any answer give no graph will receive thumb down!!!

Prepare two sketches based on the complete titration of a 10.00 mL aliquot of 0.02000 F neutral ethylenediamine (H2NCH2CH2NH2) with 0.0500 F titrant: Plot 1) pH vs mL titrant added Plot 2) fractional composition (a) vs. pH (0-14) for all ethylenediamine-derived species in solution. Indicate on your plots: . On Plot 1: o Which titrant was used: NaOH or HCI. The initial pH. The pH at the half-equivalence point(s) and equivalence point(s). • On Plot 2: A legend to indicate which line describes which species (colours or patterns are appropriate). • Units and labels for all axes (and scale them appropriately to maximize the plot visibility). These are sketches as demonstrated in class - your plots (outside the indicated points) do not have to be 100% accurate, but match the approximate pH (or fraction) and general shape of the curve expected.

Answer 1

Plot i) Here, the titrant is acid (HCl) because the titrand (ethylenediamine) is a weak base.

More the HCl added, the greater is the decrease in pH.

Lesser the HCl added, the smaller is the decrease in pH.

i.e. The pH decreases by keep on adding the titrant (HCl), hence the curve starts from some upper point and lowers down.

Plot ii) At lower pH values, the fractional composition [NH2CH2CH2NH3⁺]/[NH2CH2CH2NH2] and [NH3⁺CH2CH2NH3⁺]/[NH2CH2CH2NH2] increases, whereas at higher pH, those values decrease.