MATTER

Matter is anything that has mass and takes up space.

Mass is a measure of the amount of matter in an object.

4 forms of matter solid liquid gas plasma

solid liquid gas

SOLIDS

A solid has a definite shape and takes up a definite volume or space.

In a solid the particles vibrate but do not move around.

2 groups of solids crystal amorphous

crystal particles are arranged in a regular, repeating three-dimensional pattern.

This organized structure is called a crystal lattice, which is created when a solid of pure elements or compounds freezes.

has particles which are jumbled together amorphous has particles which are jumbled together

It lacks a regular, repeating pattern

To change a solid into a liquid, a form of energy must be added to have the atoms move faster.

LIQUIDS

Liquids have a definite volume but not a definite shape.

Forces between the particles in liquids are farther apart and not strong enough to hold a liquid in any definite shape.

To change a liquid into a gas, an energy source must be added.

GAS

A gas does not have a definite shape or volume.

Gas particles are very far apart compared to those of a liquid or a solid.

The forces between the gas particles are very weak.

Gas particles move quickly in straight lines, changing direction when they collide with each other or hit the walls of a container.

A gas can be subjected to an energy source and changed into a plasma.

PLASMA

The sun and other stars are in a plasma state.

Plasma particles shake violently at very high temperatures and are electrically charged.

Substances can be changed from one state to another.

Particles are held together by forces Particles are held together by forces. These forces give a solid its definite shape.

PHYSICAL PROPERTIES OF MATTER

Physical properties are characteristics of matter that can be studied without changing the make-up of a substance.

Color, taste, odor, and melting temperature are physical properties.

The physical properties of a kind of matter stay the same regardless of the shape or amount of that matter.

a liquid’s resistance to flow viscocity a liquid’s resistance to flow

Water has a LOW viscocity and flows EASILY Water has a LOW viscocity and flows EASILY. Motor oil has a HIGH viscocity and flows SLOWLY.

SURFACE TENSION

Surface tension is the tendency of a liquid to form a skin at the surface as the particles move closer together.

moving together of particles of the same substance cohesion moving together of particles of the same substance

moving together of particles of different substances adhesion moving together of particles of different substances

PROPERTIES OF SOLIDS

elasticity quality of a solid to be stretched and then return to its original shape

can be hammered into thin sheets malleable solids can be hammered into thin sheets

brittleness break when hammered

ability of a solid to resist being scratched hardness ability of a solid to resist being scratched

ability of a solid to be drawn into a wire ductility ability of a solid to be drawn into a wire

how well a solid resists breaking under tension tensile strength how well a solid resists breaking under tension

Knowledge of the physical properties help people choose the best ways to use different types of matter.

CHANGES OF STATE

The temperature at which changes take place are physical changes.

temperature at which a solid becomes a liquid melting point temperature at which a solid becomes a liquid

temperature which a liquid returns to or becomes a solid freezing point temperature which a liquid returns to or becomes a solid

The point at which a substance melts or freezes depends on how strong the forces are that attract their particles.

A liquid can change to a gas state by evaporation or by boiling.

Evaporation takes place at the surface of a liquid.

Boiling takes place all through a liquid.

The boiling point is the temperature at which a liquid boils at sea level.

Condensation is the reverse of boiling.

In evaporation, a liquid turns into a gas In evaporation, a liquid turns into a gas. In condensation, a gas (water vapor) turns into a liquid.

The temperature at which a gas condenses and changes to a liquid is called the condensation point.

A physical change is one in which the appearance of matter changes, but its chemical properties remain the same.

Physical changes melting grinding freezing compressing boiling cutting grinding compressing expanding

Burning causes chemical changes in matter.

A chemical change is a change that produces one or more kinds of matter different from those present before the change.

Mixtures, Solutions, and Compounds

A mixture is formed when two or more substances that can be physically separated is produced.

A mixture has a definite line separating the layers of the different substances.

A solution is made when one or more liquid, gaseous, or solid substance is dispersed in another.

A solution has small pieces of one substance intermixed with pieces of another substance.

A compound exists when 2 or more elements are chemically bonded together.

A compound joins together molecules of more than one element to create a new substance.

EXAMPLES

MIXTURE vinegar/ water oil/ water sand/water

SOLUTION sugar/ water drink mix/water

COMPOUND Iron/ oxygen (iron oxide, rust) sodium/ chloride (salt) hydrogen/ oxygen (water)

Chemical reactions can cause a change in temperature.

Exothermic reactions transfer energy to the surroundings making it get hotter.

An example would be a hand warmer An example would be a hand warmer. The chemical reaction creates heat which warms the area.

Endothermic reactions take in energy making the surroundings colder.

An example would be an instant ice pack An example would be an instant ice pack. The chemical reaction cools the surrounding area.

Acids and Bases

Scientists use something called the pH scale to measure how acidic or basic a liquid is.

The scale goes from 0-14.

Acids are found between 0 and 6 on the scale Acids are found between 0 and 6 on the scale. Bases are located from 8 to 14 on the scale.

0-6 7 8-14 acids neutral bases pH scale

The pH of a liquid is based on the number of positive (+) hydrogen molecules and the number of negative (-) hydroxide molecules in it.

If there is a high number of positive hydrogen molecules, the liquid has a low pH.

If a liquid has a high number of hydroxide molecules in it, it has a high pH.

Acid is a liquid that has a high volume of hydrogen molecules.

A base would be a liquid that has a high number of hydroxide molecules.

Strong acids are acids, which have a very low pH (0-4) Strong acids are acids, which have a very low pH (0-4). Strong bases have a very high pH (10-14).

Weak acids have a pH between 3 and 6 Weak acids have a pH between 3 and 6. Weak bases have pH values between 8-10.

Acids v neutralize bases v taste sour v react with many metals to make hydrogen v conduct electricity

Acid Uses v water treatment v  household cleaners v glass and metal etchings v used in batteries v production of synthetic fibers

Bases v neutralize acids v taste bitter vfeel slippery vconduct electricity

uses for bases : v glass production v soap v milk of magnesia v mortar

Chemically reactive paper is called litmus paper.

If the paper turns red, the substance is acidic If the paper turns red, the substance is acidic. If the paper turns blue, the substance is a base. No change would, of course, indicate that the material is neutral.

Material that changes color because of a chemical reaction is called a chemical indicator.