Question

which statement about gases is true?

they are made up of particles that travel in a curved path when in motion.
they are made up of hard spheres that are in random motion.
they are made up of hard spheres that vibrate quickly in stationary positions.
they are made up of particles that always move very slowly.

Explanation:

Analyze the motion of gas particles

According to the kinetic molecular theory, gas particles travel in straight-line paths, not curved paths, until they collide with other particles or the walls of their container.

Evaluate the random motion model

The kinetic molecular theory models gas particles as hard spheres that are in constant, rapid, and random motion.

Assess stationary and slow motion options

Gas particles do not vibrate in stationary positions (which describes solids) and they move rapidly at normal temperatures rather than always moving very slowly.

Answer:

• (A) They are made up of particles that travel in a curved path when in motion.
• (B) They are made up of hard spheres that are in random motion. (Correct answer)
• (C) They are made up of hard spheres that vibrate quickly in stationary positions.
• (D) They are made up of particles that always move very slowly.