Biochemistry Chapter: Buffer Systems and Properties

<p>pH increases as H+ ions are removed (B)</p> Signup and view all the answers

<p>It disturbs the structure and creates local order. (D)</p> Signup and view all the answers

<p>Density change (A)</p> Signup and view all the answers

<p>Renal regulation (C)</p> Signup and view all the answers

<p>pH decreases due to increased H+ concentration (D)</p> Signup and view all the answers

<p>Solutes make it more difficult for water to freeze. (B)</p> Signup and view all the answers

<p>The pressure at which the liquid and gas phases are in equilibrium. (C)</p> Signup and view all the answers

<p>Neutralizing fixed acids (D)</p> Signup and view all the answers

<p>They promote a net decrease in order of water molecules. (A)</p> Signup and view all the answers

<p>By storing substances like sugars in polymeric form. (C)</p> Signup and view all the answers

<p>Boiling point increases. (B)</p> Signup and view all the answers

<p>The solute concentration in the solution. (B)</p> Signup and view all the answers

<p>H+ ions (B)</p> Signup and view all the answers

<p>It acts as a base. (A)</p> Signup and view all the answers

<p>Conjugate base (C)</p> Signup and view all the answers

<p>It donates a proton. (B)</p> Signup and view all the answers

<p>NH3 (B)</p> Signup and view all the answers

<p>The substance that remains after an acid donates a proton. (A)</p> Signup and view all the answers

<p>Brønsted-Lowry theory allows for reactions outside of water. (D)</p> Signup and view all the answers

<p>Hydronium ion (A)</p> Signup and view all the answers

<p>A conjugate acid (A)</p> Signup and view all the answers

<p>7 (C)</p> Signup and view all the answers

<p>Kw increases with an increase in temperature. (A)</p> Signup and view all the answers

<p>pH + pOH = 14 (D)</p> Signup and view all the answers

<p>[H+] is equal to [OH-] (B)</p> Signup and view all the answers

<p>Reacts with metals to produce H2 (C)</p> Signup and view all the answers

<p>The solution is acidic. (B)</p> Signup and view all the answers

<p>H2O (l) ↔ H+ (aq) + OH- (aq) (A)</p> Signup and view all the answers

<p>1.0 x 10-14 (A)</p> Signup and view all the answers

<p>pH decreases. (B)</p> Signup and view all the answers

<p>A salt and water are produced. (B)</p> Signup and view all the answers

<p>Strong acids completely dissociate into their ions when mixed with water. (D)</p> Signup and view all the answers

<p>HCl and Cl ̶ (C)</p> Signup and view all the answers

<p>$4.79 imes 10^{-4} ext{ M}$ (A)</p> Signup and view all the answers

<p>Weak acids create an equilibrium in their dissociation. (B)</p> Signup and view all the answers

<p>They completely dissociate into their ions. (C)</p> Signup and view all the answers

<p>pH = -log [H3O+] (A)</p> Signup and view all the answers

<p>$1.12 imes 10^{-6} ext{ M}$ (B)</p> Signup and view all the answers

<p>H2SO4 (A)</p> Signup and view all the answers

A measure of disorder or randomness in a system. Higher entropy indicates more disorder.

The tendency for water molecules to become more ordered in the presence of solutes, regardless of whether the solutes are polar or nonpolar.

Properties of a solution that depend on the concentration of solute particles, not their specific identity.

The decrease in the freezing point of a solvent when a solute is added.

The increase in the boiling point of a solvent when a solute is added.

The decrease in the vapor pressure of a solvent when a solute is added.

The pressure that needs to be applied to a solution to prevent the inward flow of water across a semipermeable membrane.

Storing substances as polymers, like glycogen or starch, reduces the osmotic pressure they exert on cells, preventing excessive water influx.

A substance that releases hydrogen ions (H+) when dissolved in water. For example, hydrochloric acid (HCl) dissociates into H+ and Cl- ions in water.

A substance that releases hydroxide ions (OH-) when dissolved in water. For example, sodium hydroxide (NaOH) dissociates into Na+ and OH- ions in water.

A more general definition of acids and bases that applies to reactions in solutions other than water. An acid is a proton (H+) donor, and a base is a proton (H+) acceptor.

A hydrogen-containing species that donates a proton (H+) in a chemical reaction. For example, HCl is a Brønsted-Lowry acid because it donates a proton to water.

A species that accepts a proton (H+) in a chemical reaction. For example, water is a Brønsted-Lowry base because it accepts a proton from HCl.

The species formed when an acid loses a proton. For example, Cl- is the conjugate base of HCl.

The species formed when a base gains a proton. For example, H3O+ is the conjugate acid of H2O.

A chemical reaction where an acid and a base react to form a salt and water. For example, HCl (acid) + NaOH (base) → NaCl (salt) + H2O (water).

A substance that can act as both an acid and a base. For example, water can act as an acid in the presence of a stronger base and a base in the presence of a stronger acid.

The autoionization of water is the process where two water molecules react to form a hydronium ion (H3O+) and a hydroxide ion (OH-). The equilibrium of this reaction lies far to the left, meaning that there are very few ions present in pure water.

A solution is considered neutral when the concentration of hydrogen ions (H+) is equal to the concentration of hydroxide ions (OH-).

A solution is considered acidic when the concentration of hydrogen ions (H+) is greater than the concentration of hydroxide ions (OH-).

A solution is considered basic when the concentration of hydrogen ions (H+) is less than the concentration of hydroxide ions (OH-).

pH is a measure of the acidity or basicity of a solution. It's calculated as the negative logarithm of the hydrogen ion concentration.

The ionization constant of water (Kw) is a measure of the extent to which water autoionizes at a given temperature. It is the product of the hydrogen ion concentration and hydroxide ion concentration.

At 25°C, the product of the hydrogen ion concentration and hydroxide ion concentration in pure water is equal to 1.0 x 10^-14. This means that the pH of pure water is 7.

pKw is the negative logarithm of the ionization constant of water (Kw). It is related to pH and pOH by the equation pKw = pH + pOH.

pOH is the negative logarithm of the hydroxide ion concentration. It is related to pH and pKw by the equation pKw = pH + pOH.

Chemists were interested in grouping substances based on their shared characteristics. They observed that many substances could be categorized into two groups: acids and bases.

A Brønsted-Lowry acid donates a proton (H+) to a Brønsted-Lowry base, which accepts the proton. The acid becomes a conjugate base after donating a proton, and the base becomes a conjugate acid after accepting a proton.

A strong acid ionizes completely in solution, meaning all of its molecules donate a proton (H+) to form ions. This is represented by a single arrow in a chemical equation.

A weak acid only partially ionizes in solution, meaning only a small fraction of its molecules donate a proton (H+). This is represented by double arrows in a chemical equation to show equilibrium.

A strong base completely dissociates in water to form its cation and hydroxide ion (OH-). Examples include Group I and II metal hydroxides.

pH is a measure of the acidity or alkalinity of a solution. It is calculated using the formula: pH = -log[H3O+]. A lower pH indicates a higher acidity, while a higher pH indicates a higher alkalinity.

pOH is a measure of the hydroxide ion concentration in a solution. It is calculated using the formula: pOH = -log[OH-]. A lower pOH indicates a higher alkalinity, while a higher pOH indicates a higher acidity.

The relationship between pH and pOH is given by the equation: pH + pOH = 14. This equation holds true for aqueous solutions at 25°C.

To calculate the molarity of hydrogen ions ([H+]) in a solution, use the formula: [H+] = 10^-pH. The number of decimal places in the log answer equals the number of significant figures in the molarity.

To calculate the molarity of hydroxide ions ([OH-]) in a solution, use the formula: [OH-] = 10^-pOH. The number of decimal places in the log answer equals the number of significant figures in the molarity.

Knowing either the pH or pOH of a solution allows you to calculate all other values related to acidity and alkalinity, including [H+], [OH-], and pOH or pH, respectively.

A chemical system that resists changes in pH by either accepting or donating hydrogen ions (H+).

The most important buffer system in the intracellular fluid (ICF).

The most important buffer system in the extracellular fluid (ECF) and is responsible for transporting carbon dioxide (CO2) in the blood.

A buffer system that relies on protein molecules, amino acids, and hemoglobin to help maintain pH balance.

The primary regulator of pH in the body, adjusting blood pH by eliminating excess acids and bases through urine.

A system that regulates pH by controlling CO2 levels through breathing. This is a fast but temporary solution.

The process of regulating pH by altering the rate and depth of breathing. Rapid, deep breathing removes CO2, leading to an increase in pH.