How is the pI calculated for Glycine (Gly)?
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pI = (pK1 + pK2) / 2, where pK1 = 2.3 and pK2 = 9.6.
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How is the pI calculated for Glycine (Gly)?
pI = (pK1 + pK2) / 2, where pK1 = 2.3 and pK2 = 9.6.
What are the pKa values for the phosphate buffering system?
pKa1 = 2.15, pKa2 = 7.2, pKa3 = 12.4.
According to Arrhenius, what is the definition of an acid?
A donor of H+ ions.
What is the chemical equation for the conversion of H2CO3 to CO2 and H2O?
H2CO3 ↔ CO2 + H2O
What are the phosphate and bicarbonate buffering systems in the body?
They are important systems that help maintain the pH balance in the body by resisting changes in pH.
What happens to the partial pressure of CO2 in the lungs when holding your breath or breathing into a paper bag?
It increases above normal levels.
What is the Chloride Shift?
The movement of chloride ions into the cell as bicarbonate ions move out.
What does the Henderson-Hasselbalch equation explain?
How a change in acid or base concentration affects the pH.
What is the concept of buffering?
Buffering refers to the ability of a solution to resist changes in pH when an acid or base is added.
What is the equation for pH in terms of pKa, [A-] and [HA]?
pH = pKa + log 10 [A-] / [HA]
What does a larger K a (or K b) value indicate?
More dissociation.
Why are phosphate species usually paired with other cations?
They are often paired with other cations, often Na+.
According to Arrhenius, what is the definition of a base?
A donor of OH- ions.
What is the expression for K b in terms of concentrations?
[BH][MOH] / [MB]
What is the Henderson-Hasselbalch equation?
pH = pKa + log10 [A-]/[HA]
What happens when added OH- reacts with HA in a buffer solution?
It causes a shift to the right in the equilibrium position.
How do pH and pKa relate?
When pH > pKa, the species is in the conjugate base (unprotonated) form.
What is formed when remaining protons interact with HPO4^2-?
H2PO4^- (NaH2PO4).
How do competitive short-distance runners raise their blood pH before starting?
By hyperventilating for about 30 seconds to remove CO2 from their lungs.
How does the Chloride Shift affect the hematocrit levels in venous blood?
It causes venous hematocrit to be approximately 3% higher than arterial hematocrit.
What is the chemical equation for the dissociation of a weak base?
MB (aq) + H2O (l) ↔ BH+ (aq) + MOH- (aq)
What are the pK values for the titration of Lysine (Lys)?
pK1 = 2.2, pK2 = 9.0, pK3 = 10.5.
What does K D represent in the given equation?
The equilibrium constant for the reaction.
What is the term for having more than one pKa value for polyprotic acids?
Polyprotic acids have more than one pKa value.
How can the partial pressure of CO2 in the lungs be varied rapidly?
By the rate and depth of breathing.
What happens to the blood pH of competitive short-distance runners after hyperventilating?
It rises to pH 7.60.
What is the expression for K a in terms of concentrations?
[BH][MOH] / [MB]
What is the equation for pH in terms of pKa, [HCO3-] and [H2CO3]?
pH = pKa + log 10 [HCO3-] / [H2CO3]
What is the mathematical relationship between hydrogen ion concentration and hydroxide ion concentration in a solution?
[H + ] x [OH - ] = 10^-14
What is the major buffering system for urine and intracellular fluid?
Phosphate Buffering System.
What are the two main phosphate species involved in the buffering system?
Dihydrogen phosphate and Monohydrogen phosphate.
What is the role of Band 3 in the Chloride Shift?
It acts as a bicarbonate ion/chloride antiporter.
According to Bronsted-Lowry, what is the definition of an acid?
A donor of H+ ions.
What is the expression for K D in terms of reactants and products?
[Products] / [Reactants]
What is the definition of pI (isoelectric point)?
The pH at which a molecule carries no net charge.
What happens when dilute HCl is added to the acetate buffer?
The impact of pH change is lessened.
What is the effect of increased partial pressure of CO2 in the lungs on blood pH?
It decreases blood pH.
What happens as a lot of chloride ions move into the cell in venous blood?
It causes water to follow, resulting in swelling of the cell.
What is the chemical equation for the dissociation of a weak acid?
MB (aq) + H2O (l) ↔ BH+ (aq) + MOH- (aq)
What are some common substances used in titrations?
HCl or NaOH.
how do you calculate PI of an acid vs basic?
acid = pk1+pk2/2 basic =pk2+pk3/2
What happens when added H+ reacts with A- in a buffer solution?
It causes a shift to the left in the equilibrium position.
What is the relationship between pH and pOH?
pH + pOH = 14
Why is the pI relevant for predicting the charge of an amino acid at a given pH?
Because it indicates the pH at which the amino acid carries no net charge.
What does a small K a (or K b) value indicate?
Very little dissociation (very little [Product]).
What does a pK a (or pK b) value does not indicate?
It does NOT mean a net 0 charge between the 2 species.
Can you provide an example of a polyprotic acid with more than one pKa value?
Phosphate is an example of a polyprotic acid with more than one pKa value.
What is pH?
pH is a measure of the acidity or basicity of a solution, representing the concentration of hydrogen ions.
Where do pKa values lie on monoprotic titration curves?
At the middle of the curves.
What is the formula to calculate pH?
pH = -log[H + ]
What happens in the lungs in relation to the Chloride Shift?
As CO2 is reformed and leaves, chloride leaves the cell, causing RBCs to shrink.
According to Lewis, what is the definition of an acid?
An electron-pair acceptor.
What happens when a strong acid is added to a buffer?
The strong acid completely dissociates into its ions and the protons react with the conjugate base present to form more of the weak acid component, resulting in a slightly lower pH.
What is an acid-base buffer?
A solution that lessens the impact of pH change from the addition of acid or base.
What happens after absorption of available bicarbonate ions in tubular filtrate?
Remaining protons interact with HPO4^2- to form H2PO4^- which can be excreted in urine.
What happens when 1 mL of 1 M NaOH is added to the acetate buffer?
The impact of pH change is lessened.
What are the characteristics of strong acids and bases?
They completely ionize or dissociate into their ions.
What does a pK a (or pK b) value closer to 0 or negative indicate?
Stronger acids (or bases).
Why is the Monohydrogen phosphate considered a major species in the phosphate buffering system?
Because pKa2 is near the physiological pH of our body.
What does K b represent in the given equation?
The base dissociation constant for the reaction MB (aq) + H2O (l) ↔ BH (aq) + MOH (aq).
What is the function of the formed H2PO4^-?
Protons removed from extracellular fluid.
What are the characteristics of weak acids and bases?
They dissociate only to a limited extent.
What is the pK a (or pK b) value?
The pH value when 2 species are in equal concentration, e.g. weak acid and conjugate base.
What does K a represent in the given equation?
The acid dissociation constant for a given reaction MB (aq) + H2O (l) ↔ BH (aq) + MOH (aq).
According to Bronsted-Lowry, what is the definition of a base?
An acceptor of H+ ions.
According to Lewis, what is the definition of a base?
An electron-pair donor.
acids in the blood of a healthy individual.
why can an amino acid acts a buffer?
amine group and carboxyl group
explain the bicarbonate buffering system.
Bicarbonate Buffering System.
