Respuesta :
Answer:
Explanation:
Let the tyrosine molecule be represented by TH . It will ionise in water as follows
TH ⇄ T⁻ + H⁺
Let C be the concentration of undissociated TH and α be the degree of dissociation
TH ⇄ T⁻ + H⁺
c 0 0 ( before )
c( 1-α ) αc αc ( after ionisation)
Ka = α²c² / c( 1-α )
= α²c ( neglect α in the denominator as it is very small )
pKa = 10
Ka = 10⁻¹⁰
pH = 8.5
H⁺ = 10⁻⁸°⁵
αc = 10⁻⁸°⁵
α²c =Ka = 10⁻¹⁰
α x10⁻⁸°⁵ = 10⁻¹⁰
α = 10⁻¹⁰⁺⁸°⁵
= 10⁻¹°⁵ = 1 / 31.62
Percentage of dissociation = 100 / 31.62
= 3.16 %
percent of tyrosine side chains deprotonated
