How do molecules at higher temperatures differ from molecules at lower temperatures?

• A. They form stronger chemical bonds.
• B. They move slower and have less average kinetic energy.
• C. They move faster and have greater average kinetic energy.
• D. They have a larger mass.

Answer: (C)

Verified step by step guidance

1. Understand that temperature is a measure of the average kinetic energy of molecules in a substance.
2. Recall the kinetic molecular theory, which states that as temperature increases, the average kinetic energy of molecules increases.
3. Recognize that kinetic energy is related to the speed of molecules by the equation \(KE = \frac{1}{2}mv^2\), where \(m\) is mass and \(v\) is velocity (speed).
4. Conclude that at higher temperatures, molecules move faster because their average kinetic energy is greater.
5. Note that temperature does not affect the mass of molecules, nor does it directly cause stronger chemical bonds to form.