Physical Science

Chapter 16

Study Guide

Matter is made of atoms and takes up space.

The Kinetic Theoryexplains how particles in matter behave.

There are three assumptions to the Kinetic Theory

  1. All matter is composed of small particles.
  2. These particles are in constant, random motion.
  3. These particles are colliding with each other and the walls of their container.

There are four forms of matter. List them below.

1.

2.

3.

4.

Solids

-Matter in which particles are arranged in repeating geometric patterns

-Definite shape & definite volume

-The particles that make up a solid move more slowly than do the particles that make up gas.

Liquid

-Matter that has a definite volume but no definite shape

Gas

-Matter with no definite volume or definite shape

-Particles are free to move in all directions until they have spread evenly throughout their container

Plasma

-Most common state of matter in the universe

-No definite volume or shape

-Made up of positively and negatively charged particles

-Gas-like mixture

The amount of energy needed to change a material from a solid to a liquid is called the heat of fusion.

Liquid Crystals

-Liquids which keep some ordered structure

-Do not change states in the usual matter

Amorphous solid:

-Lack highly ordered structure found in crystals

-Glass, plastic

-Example we talked about in class: obsidian/volcanic glass

Compared to most substances water is unusual because it expands when it goes from liquid to solid (most materials contract when changing from a liquid to a solid).

Most matter expands when it is heated. This is known as thermal expansion.
As a sample of matter a heated, its particles move more quickly.

The theoretical point at which all molecular motion stops is called absolute zero.

Viscosity = a fluid’s resistance to flow

Archimedes’ Principle: The buoyant force on an object is equal to the weight of the fluid displaced by the object.

  • Determines whether an object will sink or float

An object will float if the object is less dense than the liquid in which it is placed in.

Pressure is force exerted per unit area. (P= F/A)

Pressure is recorded in the SI unit Pascals.

  • Blaise Pascal discovered a useful property of fluids
  • According to Pascal’s principle: Pressure applied to a fluid is transmitted throughout the fluid.
  • Example we talked about in class- a tube of toothpaste & hydraulic machines!

Bernoulli’s Principle: As the velocity of a fluid increases, the pressure exerted by the fluid decreases.

  • Example we used in class: chemical hose sprayer
  • How planes fly

Boyle’e Law: If you decrease the volume of a container of gas and hold the temperature constant, the pressure of the gas will increase

  • An increase in volume of the container causes the pressure to drop, if the temperature remains constant.
  • As pressure decreases, volume increases
  • P1V1 = constant = P2V2
  • This shows us that the product of the initial pressure and volumedesignated with the subscript 1is equal to the product of the final pressure and volumedesignated with the subscript 2.

Charles’ Law: the volume of a gas increases with increasing temperature provided the pressure does not change

  • Temperature must be on the kelvin scale
  • V1/T1 = V2/T2,