Physical Science Matter

What are substances made of?

Matter What is Matter? Matter is anything that takes up space and has

a mass. Can exist in any of four states under the right

conditions. They are: 1. Solid, 2. Liquid, 3. Gas, and 4. Plasma

Solid

Every solid has a definite shape and definite volume.

In most solids the particles are arranged in repeating geometric patterns. These arrangements form crystals.

Amorphous Solids

Some materials such as glass, many plastics, and some kinds of wax appear to be solid, but are not made of crystals.

These types of solids are called amorphous solids.

Amorphous means having no form. Some scientists would classify these as “very

thick liquids.”

Kinetic Theory of Matter

What accounts for the characteristics of solid matter?

Tiny particles in constant motion make up all matter.

This idea is called the kinetic theory of matter.

Solids

Solids Solids retain their

shape regardless of the container they are in.

They have a constant shape and volume.

Liquid

A liquid flows and takes the shape of its container.

Liquids can’t normally be squeezed into a smaller volume.

Liquids

Liquids have a constant volume, but will take the shape of the container they are held in.

The particles are not held in place.

Gases

They expand or contract to fill the space available to them and can be squeezed into a smaller space.

A gas has no definite shape or definite volume.

Gases

Gases do not have a constant shape and do not have a constant volume.

The particles of a gas have enough energy to spread widely apart from one another.

What causes the pressure of a gas?

Pressure is caused by the gas particles colliding with the walls of its container.

Collisions between air molecules and the inside of a balloon keep it inflated.

Pressure is the amount of force exerted per unit of area. P = F / A

The Pascal is the metric unit of pressure.

Robert Boyle

Robert Boyle (1627-1691) was a British scientist who studied and described properties of gases.

Developed a law known as “Boyle’s Law.”

Boyle’s Law

If you decrease the volume of a container of gas, the pressure will increase, provided that the temperature does not change.

Jacques Charles

Jacques Charles (1742-1823) was a French scientist who also studied gases.

Developed the law now known as “Charles’ Law.”

Charles’ Law Charles’ Law The volume of a gas increases with increasing

temperature, provided that the pressure does not change.

Kinetic Theory of Matter

Kinetic Theory of Matter As a gas is heated, its particles move faster and

faster, and its temperature increases. Because the gas particles move faster, they

begin to strike the walls of their container more often and with more force.

If the walls are free to move the gas pushes the walls out and expands.

Plasma

Plasma is a gas-like mixture of positively and negatively charged particles.

Plasma is found naturally in the sun and other stars.

Heating a substance to above 5000ºC produces plasma.

Behavior of Fluids

Particles of a fluid slide past one another and do not halt motion through the substance.

Although fluids do resist motion through the substance, i.e. fluid friction.

Archimedes’ Principle

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

The greater the density of the liquid, the greater the buoyant force.

Buoyancy

Buoyancy is the ability of a fluid—a liquid or a gas—to exert an upward force on an object

immersed in it.

Buoyant Force

If the buoyant force is less than the object’s weight the object will sink.

Buoyancy

If the buoyant force equals or exceeds the object’s weight, the object will float.

Pascal’s Principle

Pascal’s principle states that pressure applied to a fluid is transmitted, unchanged, throughout the fluid.

A hydraulic lift is a machine that makes use of Pascal’s principle.

Bernoulli’s Principle

According to Bernoulli’s Principle, as the velocity of a fluid increases the pressure exerted by the fluid decreases.

Bernoulli’s Principle

Lift Higher velocity = less pressure

Bernoulli’s Principle

Physical Properties

The state of matter of a substance is determined by its physical properties.

Physical property is a quality that can be observed or measured without changing the chemical makeup of a substance.

Physical Properties of Matter

Examples of physical properties are; (you should define each of the following)

density malleability ductility conductivity elasticity solubility

hardness color luster odor taste

texture

• taste

• texture

melting point boiling point

optical properties transparent translucent opaque

Can Matter Be Changed?

Yes, in two ways, Physical Chemical

Physical Changes

Physical Changes are changes in matter that do not change the individual chemical atoms or molecule.

Characteristics of physical changes: The shape, size or state of matter changes. No new substances with new properties are formed. Reversal of the action that caused the change may

restore the substance to its original form.

Change in State

Evaporation is a change in state.

Evaporation is the change of a substance from the liquid state to the solid state.

Evaporation happens at the surface of the liquid when liquid molecules escape into the atmosphere.

Chemical Changes

Chemical changes are changes in matter in which chemical atoms are changed and new molecules are formed.

Characteristics of chemical changes: New substances with new properties are formed. The original substances can only be restored by

chemical means. Evidence of chemical action is usually apparent; for

example, by production of light, heat, a gas, or other new substance.

Types of Matter

Element: a substance that cannot be broken down into simpler substances by ordinary chemical means. Compound: composed of two or more elements that are chemically joined or “Bonded” together.

Types of Matter

Mixture: a substance made of two or more elements or compounds that have not combined chemically with each other. Solution: a type of mixture in which the particles of both substances are evenly distributed. Typically a liquid, it can be colored or colorless, but is generally transparent to translucent.

Atoms and Elements

Chemical elements are simple forms of matter that cannot be changed into any simpler form of matter by ordinary means.

An atom is the smallest particle of an element. What is the difference? Let's use Hydrogen as an example;

Hydrogen

Hydrogen is an element that is composed of atoms.

Hydrogen is represented with a capitol H. We can find H in water, alcohol, the

atmosphere, and in many other substances. A Hydrogen atom will look like this;

Hydrogen

Hydrogen the element is comprised of many atoms, thus it will look more like this;

Elements and Atoms

Elements can be broken down into individual atoms, but atoms are the smallest particles of that element.

Atoms are made up of even smaller particles called protons, neutrons and electrons.

The Periodic Table

You will learn much more about the elements and the Periodic Table in the next unit.

Source

Compliments of Pat HayhurstLancaster High School 2000