Question

question 8 (4 points)
(01.04 mc)
the table compares the characteristics of a substance in three different states of matter.
comparison of characteristics
characteristic | state x | state y | state z
average kinetic energy of the molecules | low | greatest | least
particle attraction/forces | weak | negligible | strong
which of these best describes the state of the substance represented by state z?
○ a it is a solid because strong attractive forces prevent particles from moving.
○ b it is a liquid because strong attractive forces prevent particles from moving.
○ c it is a liquid because weak attractive forces allow for some motion.
○ d it is a gas because weak attractive forces allow for some motion.

question 9 (4 points)
(01.04 lc)
the following properties are either physical or chemical. which one is different from the rest, based on those two categories?
○ a boiling point
○ b flammability
○ c ductility
○ d density

Explanation:

Question 8

To determine the state of matter for State Z, we analyze the given characteristics:

• Average Kinetic Energy of Molecules: Least (kinetic energy is lowest in solids as particles have minimal motion).
• Particle Attraction/Forces: Strong (solids have strong intermolecular forces that hold particles in place).

Now, let's evaluate the options:

• Option a: States it is a solid because strong attractive forces prevent particles from moving. This matches the characteristics of State Z (least kinetic energy, strong forces).
• Option b: Liquids have weaker forces than solids and more kinetic energy than solids. Also, liquids do not have forces that prevent particles from moving (they can slide past each other), so this is incorrect.
• Option c: Liquids have weak forces (weaker than solids) and moderate kinetic energy. State Z has strong forces and least kinetic energy, so this is incorrect.
• Option d: Gases have negligible forces and greatest kinetic energy. State Z has strong forces and least kinetic energy, so this is incorrect.

We need to classify properties as physical or chemical:

• Physical properties: Can be observed or measured without changing the substance's chemical identity (e.g., boiling point, ductility, density).
• Chemical properties: Describe a substance's ability to undergo chemical changes (e.g., flammability, which involves combustion, a chemical reaction).

Now, let's analyze the options:

• Option a: Boiling point is a physical property (related to phase change, no chemical change).
• Option b: Flammability is a chemical property (involves burning, a chemical reaction).
• Option c: Ductility is a physical property (ability to be drawn into wires, no chemical change).
• Option d: Density is a physical property (mass per unit volume, no chemical change).

So, flammability (option b) is a chemical property, while the others are physical.

Answer:

a. It is a solid because strong attractive forces prevent particles from moving.

Question 9