Which of the following is the easiest way to add energy to matter?

• A. Heating the substance
• B. Increasing the pressure
• C. Adding a catalyst
• D. Decreasing the volume

Answer: (A)

Verified step by step guidance

1. Understand that adding energy to matter typically means increasing its internal energy, often by increasing temperature or changing its physical state.
2. Consider the effect of heating a substance: heating directly increases the kinetic energy of particles, which is a straightforward way to add energy.
3. Analyze increasing pressure: while it can affect energy, it mainly changes volume and phase rather than directly adding thermal energy.
4. Evaluate adding a catalyst: catalysts speed up reactions but do not add energy to the system themselves.
5. Consider decreasing volume: this can increase pressure and sometimes temperature, but it is less direct and often less efficient than heating for adding energy.