Background: As Figure above shows, the distance between particles is much smaller for the solid and liquid states than for the gas state. In the solid state, particles are fixed in place, while particles are more free to move in the liquid and gas states. The particles in the solid and liquid states “stick together,” but in the gas state, they move freely about the container. In general, it requires energy to separate individual particles. If we want to make a solid adopt a liquid form, we can add energy in the form of heat, increasing the temperature of the substance. Conversely, if we want to convert a substance from a gas to a liquid or from a liquid to a solid, we remove energy from the system and decrease the temperature. Pressure also plays an important role in changes of state, which will be discussed later on. We will study these difference in greater detail in the chapter States of Matter.

Situation: John is studying the different states of matter. Today, he has a matter in three states in front of him, state A, state B, and state C. State A is in solid state. State B is in liquid state. And, state C is in gaseous state. He needs to determine the properties of each state.

Question: In which state the distance between particles are smaller, state B or state C?
Answer: state B

Situation: John is studying the different states of matter. Today, he has a matter in three states in front of him, state A, state B, and state C. State A is in solid state. State B is in liquid state. And, state C is in gaseous state. He needs to determine the properties of each state.

Question: In which state the distance between particles are greater, state B or state C?
Answer: state C

Situation: John is studying the different states of matter. Today, he has a matter in three states in front of him, state A, state B, and state C. State A is in solid state. State B is in liquid state. And, state C is in gaseous state. He needs to determine the properties of each state.

Question: Would state B have less or more distance between particles than state C?
Answer: less

Situation: John is studying the different states of matter. Today, he has a matter in three states in front of him, state A, state B, and state C. State A is in solid state. State B is in liquid state. And, state C is in gaseous state. He needs to determine the properties of each state.

Question: Would state C have less or more distance between particles than state B?
Answer: more

Situation: John is studying the different states of matter. Today, he has a matter in three states in front of him, state A, state B, and state C. State A is in solid state. State B is in liquid state. And, state C is in gaseous state. He needs to determine the properties of each state.

Question: In which state the particles are more free, state A or state B?
Answer: state B

Situation: John is studying the different states of matter. Today, he has a matter in three states in front of him, state A, state B, and state C. State A is in solid state. State B is in liquid state. And, state C is in gaseous state. He needs to determine the properties of each state.

Question: In which state the particles are less free, state A or state B?
Answer: state A

Situation: John is studying the different states of matter. Today, he has a matter in three states in front of him, state A, state B, and state C. State A is in solid state. State B is in liquid state. And, state C is in gaseous state. He needs to determine the properties of each state.

Question: Would state A's particles be more free or less free than state B's?
Answer: less free

Situation: John is studying the different states of matter. Today, he has a matter in three states in front of him, state A, state B, and state C. State A is in solid state. State B is in liquid state. And, state C is in gaseous state. He needs to determine the properties of each state.

Question: Would state B's particles be more free or less free than state A's?
Answer: more free

Situation: John is studying the different states of matter. Today, he has a matter in three states in front of him, state A, state B, and state C. State A is in solid state. State B is in liquid state. And, state C is in gaseous state. He needs to determine the properties of each state.

Question: If energy is applied, state B would adopt which state, state A or state C?
Answer: state C

Situation: John is studying the different states of matter. Today, he has a matter in three states in front of him, state A, state B, and state C. State A is in solid state. State B is in liquid state. And, state C is in gaseous state. He needs to determine the properties of each state.

Question: If energy is removed, state B would adopt which state, state A or state C?
Answer: state A