Introduction
Hello Young Scientists!
For many years scientists and some concerned citizens have been debating over the how to categorize toothpaste, sand, and glass into one of the four states of matter. Your team has been asked to research this matter by the Head of the National Science Foundation (NSF). Your task, should you accept, will be to provide a logically sound and reasonable explanation as to which state of matter each of the items above belongs to. The NSF eagerly awaits the completion of your team's research, so that you can present your findings at the NSF's National Conference in April. You must meet the deadline to ensure funding for your project.
The Four Fundamental States
Solids
The particles (ions, atoms or molecules) are packed closely together. The forces between particles are strong enough so that the particles cannot move freely but can only vibrate. As a result, a solid has a stable, definite shape, and a definite volume. Solids can only change their shape by force, as when broken or cut.
Liquids
A liquid is a nearly incompressible fluid that conforms to the shape of its container but retains a (nearly) constant volume independent of pressure. The volume is definite if the temperature and pressure are constant. When a solid is heated above its melting point, it becomes liquid.
Gases
A gas is a compressible fluid. Not only will a gas conform to the shape of its container but it will also expand to fill the container. A gas has no definite shape or volume, but occupies the entire container in which it is confined. A liquid may be converted to a gas by heating at constant pressure to the boiling point.
Plasma
Like a gas, plasma does not have definite shape or volume. Unlike gases, plasmas are electrically conductive, produce magnetic fields and electric currents, and respond strongly to magnetic forces.
For many years scientists and some concerned citizens have been debating over the how to categorize toothpaste, sand, and glass into one of the four states of matter. Your team has been asked to research this matter by the Head of the National Science Foundation (NSF). Your task, should you accept, will be to provide a logically sound and reasonable explanation as to which state of matter each of the items above belongs to. The NSF eagerly awaits the completion of your team's research, so that you can present your findings at the NSF's National Conference in April. You must meet the deadline to ensure funding for your project.
The Four Fundamental States
Solids
The particles (ions, atoms or molecules) are packed closely together. The forces between particles are strong enough so that the particles cannot move freely but can only vibrate. As a result, a solid has a stable, definite shape, and a definite volume. Solids can only change their shape by force, as when broken or cut.
Liquids
A liquid is a nearly incompressible fluid that conforms to the shape of its container but retains a (nearly) constant volume independent of pressure. The volume is definite if the temperature and pressure are constant. When a solid is heated above its melting point, it becomes liquid.
Gases
A gas is a compressible fluid. Not only will a gas conform to the shape of its container but it will also expand to fill the container. A gas has no definite shape or volume, but occupies the entire container in which it is confined. A liquid may be converted to a gas by heating at constant pressure to the boiling point.
Plasma
Like a gas, plasma does not have definite shape or volume. Unlike gases, plasmas are electrically conductive, produce magnetic fields and electric currents, and respond strongly to magnetic forces.