Biochemistry Standard Reduction Potentials Quiz

The branch of biochemistry that studies the energy transformations that occur in living cells.

The energy required by living organisms like you to perform essential functions like growth, reproduction, and movement.

The process where living organisms capture energy from their surroundings to survive.

The utilization of energy by living organisms for tasks like growth, movement, and transport.

The science of energy and its transformations in the context of living organisms.

The conversion of one form of energy into another, a crucial process in living cells.

The synthesis of complex molecules from simpler ones, fueled by the chemical energy in food.

The movement of molecules across cell membranes, requiring energy for active transport.

The amount of heat needed to raise the temperature of 1 gram of water from 14.5°C to 15.5°C.

1000 calories (cal), equivalent to 4.184 kilojoules (kJ).

The change in free energy under standard conditions (25°C, 1 atm pressure, pH 7, and 1 M concentration of reactants and products).

The equilibrium constant for a chemical reaction, reflecting the ratio of product to reactant concentrations at equilibrium.

The change in free energy of a reaction under non-standard conditions, influenced by factors like temperature, pressure, and reactant/product concentrations.

ΔG°' and Ke' have an inverse relationship. When ΔG°' is positive, Ke' is less than 1, and when ΔG°' is negative, Ke' is greater than 1.

A reaction proceeds spontaneously, releasing energy, making it energetically favorable.

A reaction that requires energy input, making it energetically unfavorable.

A thermodynamically unfavorable reaction can be driven by coupling it with a favorable reaction (negative ΔG).

Enzymes facilitate coupled reactions, bringing the reactants together at the active site and providing a favorable environment for the reaction to occur.

A chemical reaction involving the transfer of electrons from one molecule (the electron donor) to another (the electron acceptor).

The molecule that gains electrons and is reduced in a redox reaction.

The molecule that loses electrons and is oxidized in a redox reaction.

The potential difference between two half-cells in a redox reaction, measured in volts (V).

The standard redox potential when the concentrations of the oxidized and reduced forms of a molecule are equal.

The difference in standard redox potentials between two half-cells in a redox reaction. It determines the spontaneity of the reaction.

The free energy change associated with a redox reaction, calculated using the Nernst equation.

A mathematical equation that relates the standard free energy change, the change in redox potential, and other factors like temperature and concentration.

A redox reaction is spontaneous (negative ΔG') when the Eo' of the electron acceptor is more positive than the Eo' of the electron donor, meaning there is a positive ΔEo'.

A redox reaction is non-spontaneous (positive ΔG') when the Eo' of the electron acceptor is more negative than the Eo' of the electron donor, meaning there is a negative ΔEo'.

The standard reduction potential (E°') is a measure of the tendency of a chemical species to gain electrons and be reduced. In biochemistry, it's usually measured at pH 7 and 25°C, denoted as E°′.

A more positive E°′ indicates a greater tendency for the species to be reduced (gain electrons).

A more negative E°′ indicates a lesser tendency for the species to be reduced. These species tend to be oxidized (lose electrons).

The difference between the E°′ values of two half-reactions determines the standard free energy change (ΔG°′) for a reaction.

The standard free energy change (ΔG°′) represents the energy available for doing work under standard conditions.

The actual free energy change (ΔG) is determined by the actual concentrations of reactants and products, not just standard conditions.

A property of a system that measures its tendency to change spontaneously. It combines enthalpy (heat) and entropy (disorder) to determine if a reaction will occur.

Reflects the energy change of a reaction under biological conditions (pH 7.0). It is differentiated from standard free energy (ΔG°) by the use of a prime symbol (ΔG′).

The change in free energy of a reaction in living organisms at the standard conditions of pH 7.0 and 25 °C. It incorporates the biological context for more accurate energy calculations.

A measure of a reaction's tendency to proceed to completion under standard conditions (pH 7). It represents the ratio of products to reactants at equilibrium. A high Ke′ indicates the reaction strongly favors product formation.

The energy change of a reaction that occurs spontaneously without any input of energy. It's the difference between energy states of reactants and products during a spontaneous reaction.

The energy change of a reaction that does not occur spontaneously. It requires an input of energy to proceed.

The state where the forward and reverse rates of a reaction are equal, resulting in no net change in concentrations of reactants and products.