the minimum amount of energy required for a reaction to take place is

1. Analyze the question The question asks for the name of the minimum energy that reacting particles must have before a reaction can occur.

2. Explain the concept For a chemical reaction to happen, reactant particles must collide with enough energy to break existing bonds and form new ones. This threshold energy is called the activation energy (Ea).

• Particles with energy below Ea collide but simply bounce off without reacting.
• Particles with energy equal to or above Ea can react.
• A catalyst works by providing an alternative pathway with a lower activation energy, so more particles can react.

3. Check each option

• A. Lattice energy: the energy released when gaseous ions form one mole of an ionic crystal lattice. It has nothing to do with starting a reaction.
• B. Ionization energy: the energy needed to remove an electron from a gaseous atom. It is a property of atoms, not a reaction threshold.
• C. Activation energy: the minimum energy needed for reactants to be converted into products. This matches the question exactly.
• D. Kinetic energy: the energy of motion of particles. It is a general form of energy, and it isn't defined as a minimum requirement for a reaction.

4. Answer The correct option is C. activation energy.

5. Exam tip Link the words: "Activation" = "Activate" = "get the reaction started." Whenever you see "minimum energy needed for a reaction," think of the energy-profile diagram. Activation energy is the height of the "hill" the reactants must climb before becoming products.