Which of the following increases the kinetic energy of particles in a substance?

Kinetic energy in particles is directly related to their motion; as temperature increases, the average kinetic energy of the particles in a substance also increases. This relationship arises from the fact that temperature is a measure of the thermal energy of a system, which directly correlates with the movement and vibration of particles.

When you increase the temperature of a substance, the particles gain energy, causing them to move more vigorously. This increased movement results in higher kinetic energy. For instance, heating up water causes its molecules to move faster, transitioning from a lower energy state (like ice) to a higher energy state (like steam), where the particles are not only moving faster but also are farther apart due to the increase in energy.

In contrast, decreasing temperature would lower the kinetic energy as particles would move less. Increasing pressure can affect the states of matter but does not inherently increase kinetic energy. Similarly, changing from solid to liquid (the process of melting) involves an increase in potential energy more significantly than kinetic energy until the substance reaches a certain temperature where kinetic energy begins to increase with heat added. Thus, increasing temperature is the key factor that boosts the kinetic energy of particles.