What is Gibbs free energy?
A. The energy lost as heat to the surrounding molecules
B. The usable energy released or absorbed by a reaction
C. The energy in the form of kinetic energy in a system
D. The energy contained within the bonds of molecules
http://hyperphysics.phy-astr.gsu.edu/hbase/thermo/helmholtz.html
or better:
https://www.boundless.com/biology/textbooks/boundless-biology-textbook/metabolism-6/potential-kinetic-free-and-activation-energy-69/free-energy-345-11482/
You do not need the s on https
http://www.boundless.com/biology/textbooks/boundless-biology-textbook/metabolism-6/potential-kinetic-free-and-activation-energy-69/free-energy-345-11482/
The correct answer is B. Gibbs free energy is the usable energy released or absorbed by a reaction. It is a thermodynamic potential that measures how much energy is available to do useful work at a constant temperature and pressure.
To understand Gibbs free energy, we need to consider the concept of entropy (S) and enthalpy (H). Entropy is a measure of the randomness or disorder of a system, while enthalpy is the total heat content of a system.
Gibbs free energy (G) is related to entropy and enthalpy through the equation:
G = H - TS
where T is the temperature in Kelvin. In this equation, the change in free energy (∆G) determines whether a reaction is spontaneous or requires an input of energy.
If ∆G is negative, it means the reaction is exergonic and can proceed spontaneously, releasing usable energy. On the other hand, if ∆G is positive, the reaction is endergonic and requires an input of energy to proceed.
So, Gibbs free energy helps us determine the feasibility and spontaneity of a chemical reaction, and whether it can release useful energy or not.