Berkeley Review Chem ch4 passage13 q88
"The carbon chain associated with aspartic acid is shorter than the one associated with glutamic acid, which results in a:
A . stronger inductive effect, making aspartic acid's side chain more acidic.
B. weaker inductive effect, making aspartic acid's side chain more acidic."
Would the shorter carbon chain (less hydrogens thus less electron density) produce a weaker inductive effect, or would the closer protonated amino group [(NH3+)- ] (more electronegative nitrogen) produce a stronger inductive effect? Which one is more important in this situation and why?!
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Berkeley Review Chem ch4 passage13 q90
"What is the normality of 0.50 M glutamic acid in water?
B. 1.00N H3N+CH(CH2CH2CO2H)CO2H(aq)
C. 1.50N H3N+CH(CH2CH2CO2H)CO2H(aq)"
Passage info on glutamic acid: pKa1=1.8-2.6 pKa2=4.32 pKa3=8.8-10.6
The BR answer is c because glutamic acid is triprotic. However, wouldn't water (a neutral pH solvent) only deprotonate the acid twice? Thus the acid would only be diprotic "in water" as the question asked, right?
Please help!! These crazy questions are driving me... CRAZY!!
"The carbon chain associated with aspartic acid is shorter than the one associated with glutamic acid, which results in a:
A . stronger inductive effect, making aspartic acid's side chain more acidic.
B. weaker inductive effect, making aspartic acid's side chain more acidic."
Would the shorter carbon chain (less hydrogens thus less electron density) produce a weaker inductive effect, or would the closer protonated amino group [(NH3+)- ] (more electronegative nitrogen) produce a stronger inductive effect? Which one is more important in this situation and why?!
___________________________________
Berkeley Review Chem ch4 passage13 q90
"What is the normality of 0.50 M glutamic acid in water?
B. 1.00N H3N+CH(CH2CH2CO2H)CO2H(aq)
C. 1.50N H3N+CH(CH2CH2CO2H)CO2H(aq)"
Passage info on glutamic acid: pKa1=1.8-2.6 pKa2=4.32 pKa3=8.8-10.6
The BR answer is c because glutamic acid is triprotic. However, wouldn't water (a neutral pH solvent) only deprotonate the acid twice? Thus the acid would only be diprotic "in water" as the question asked, right?
Please help!! These crazy questions are driving me... CRAZY!!