Concept explainers
Ethylenediamine (NH2CH2CH2NH2, abbreviated en) is an organic base that can accept two protons:
(a) Consider the titration of 30.0 mL of 0.100 M ethylenediamine with 0.100 M HCl. Calculate the pH after the addition of the following volumes of acid, and construct a qualitative plot of pH versus milliliters of HCl added:
(i) 0.0 mL
(ii) 15.0 mL
(iii) 30.0 mL
(iv) 45.0 mL
(v) 60.0 mL
(vi) 75.0 mL
(b) Draw the structure of ethylenediamine, and explain why it can accept two protons.
(c) What hybrid orbitals do the N atoms use for bonding?
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Chapter 15 Solutions
General Chemistry: Atoms First
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