MATTER8/22

Matter

Matter is…. Anything that has mass and takes up

space (mass and volume)

States of Matter

States of Matter

3 Main states of matter Solid Liquid Gas

Scientists recognize a fourth state of matter called plasma, but it does not occur naturally on Earth except in the form of lightning bolts.

Solid

A solid -definite shape and volume. Wood, iron, paper, and sugar are

examples of solids

The particles in a solid are very tightly packed; when heated, a solid expands, but only slightly.

Do you think a solid would conform to the shape of its container? Not Likely

Liquid

A liquid is a form of matter that flows, has constant volume, and takes the shape of its container water, blood, and mercury

The particles in a liquid are not rigidly held in place and are less closely packed than are the particles in a solid: liquid particles are able to move past each other.

Liquid

A liquid -flows, has constant volume, and takes the shape of its container water, blood, and mercury

The particles are not rigidly held in place and are less closely packed than the particles in a solid

liquid particles are able to move past each other.

Does a liquid take the shape of its container?

Gas

A gas -conforms to the shape of its container and fills the entire volume of its container.

the particles of gases are very far apart.

gases are easily compressed.

What can happen between these states?

Phase Changes

Phase changes occur when substances undergo change in temperature and pressure

Changes in States

Solid Liquid Melt

Liquid Gas Evaporate/Vaporize

Gas Liquid Condense

Liquid Solid Freeze

Solid Gas Sublime

Gas Solid Deposit

Physical/Chemical Properties

Physical Properties

Characteristics that can be observed without altering the identity of the substance. (First observation) State, density, color, odor,

melting point, boiling point, luster, conductivity, brittleness, malleability.

Chemical Properties

Characteristics that cannot be observed without altering the identity of the substance. (Something turns into something else) Reactivity, flammability, reaction types

Similarly, the inability of a substance to change into another substance is also a chemical property.

For example, when iron is placed in nitrogen gas at room temperature, no chemical change occurs.

The fact that iron does not undergo a change in the presence of nitrogen is another chemical property of iron.

Physical Changes

Physical Changes Do not alter the identity of a

substanceCrushing, tearing, changes of state (solid to liquid to gas)

** Dissolving a solid in liquid (reversible)**

Can you think of any others?

Chemical Changes

Chemical Changes Alter the identity or chemistry of

a substanceBurn, cook, rust, reacts with, explode, oxidize, corrode, tarnish, ferment, or rot: Terms that generally refer to a chemical reaction

Chemical Changes

A chemical change is the same thing as a chemical reaction

The new substances formed in the reaction have different compositions and different properties from the substances present before the reaction occurred.

Here’s an example

When a freshly exposed iron surface is left in contact with air, it slowly changes into a new substance, namely, the rust.

Rust is a chemical combination of iron and oxygen.

In chemical reactions, the starting substances are called reactants and the new substances that are formed are called products.

So in the rusty nail problem, what are the reactants and what are the products? Reactants: Iron and Oxygen Product: Rust

Even though old substances become new substances, THE MASS STAYS THE SAME BEFORE

AND AFTER THE REACTION!!!!

Conservation of Mass

Mass is never created or destroyed by a reaction! It is conserved! (This is a LAW)

The total mass in a reaction remains constant.

Mass Reactants = Mass Products

How could you find this? Measure mass of reactants and mass of

products and compare…they should be equal.

Mass of the turkey, lettuce, mayo, tomato, and bread = mass of sandwich

Note Quiz

Get out 1 piece of paper per table. Write both your names on it and work together! You will turn this in as a quiz grade.

Note Quiz

Identify each of the following as a property of a solid, liquid, or gas. Some answers will include more that one state of matter.

1. Flows and takes the shape of a container

2. Compressible3. Made of particles held in a tightly

packed, specific arrangement

4. Has definite volume5. Always occupies the entire space of

the container6. Has a definite volume but the

particles flow7. Phase change from solid liquid8. Phase change from gas liquid

Notes Quiz

Identify each of the following as an example of a chemical change or a physical change.

9. Moisture in the air forms beads of water on a cold windowpane.

10. An electric current changes water into hydrogen and oxygen