Definition

1. Noun:
   • The minimum amount of energy required to initiate a chemical reaction or a physical process: The "energy of activation" is a specific quantity of energy that must be supplied to a system of atoms or molecules to allow a particular process, such as a chemical reaction or a particle emission, to begin.

Usage

• The term is used primarily in the fields of chemistry and physics to describe a critical threshold in reaction kinetics.
• It explains why some reactions require heat or other energy sources to start, even if they are ultimately energetically favorable.

Examples

• Noun:
  • A catalyst works by lowering the energy of activation for a reaction, allowing it to proceed faster.
  • The high energy of activation explains why this compound is stable at room temperature.

Advanced Usage

• "To overcome the energy of activation": To supply sufficient energy to meet or exceed this minimum threshold.
  • The spark provided the necessary heat to overcome the energy of activation for the combustion reaction.

Variants and Related Words

• Activation Energy (n): This is the most common synonym and variant form. The terms "energy of activation" and "activation energy" are used interchangeably in scientific literature.
  • The activation energy for this step was calculated from the experimental data.

Synonyms

• Activation Energy: The minimum energy needed for a reaction to occur.

Related Concepts (Not Phrasal Verbs or Idioms)

• Transition State: The high-energy, unstable state that reactants pass through during the conversion to products.
• Reaction Coordinate: A measure of the progress of a reaction, often plotted against energy to show the activation barrier.
• Catalyst: A substance that increases the rate of a reaction by lowering the energy of activation.

Noun

1. the energy that an atomic system must acquire before a process (such as an emission or reaction) can occur
   • catalysts are said to reduce the energy of activation during the transition phase of a reaction