Can a reaction with a negative ΔG proceed spontaneously?

A reaction with a negative ΔG indicates that the process is thermodynamically favorable, meaning that it has the potential to proceed spontaneously. However, spontaneous does not imply that the reaction will occur immediately or without any intervention. There are factors such as activation energy that can affect the rate at which a reaction occurs.

For instance, some reactions with a negative ΔG might require an input of energy to get started, which is often referred to as overcoming the activation energy barrier. Additionally, concentration, temperature, and the presence of catalysts are conditions that can influence whether the reaction will proceed. Therefore, while a negative ΔG suggests that the reaction can happen spontaneously, it can only do so under suitable conditions.

Thus, the notion that a reaction may proceed spontaneously only under certain conditions fits well with the principles of thermodynamics and kinetics in chemistry.