Physical Science EXAM

JHS 8th grade Physical Science 2023-2024 EXAM!

Periodic Table

When elements are arranged this way, similarities in their properties will occur in a regular pattern.

Periods

Rows

Groups

Columns

Elements in same group have…

Similar Properties.

80% of the Periodic table are…

Metals.

Periodic

Repeating pattern.

Russian Chemist and teacher working on a way to classify elements. He studied physical and chemical properties of more than 60 elements.

Dimitri, Mendaleyev.

Charles’s Law

For a fixed amount of gas at a constant pressure, the volume of the gas increases as it’s temperature increases.

Gay-Lussac’s Law

The pressure of a gas increases as the temperature increases if the volume of the gas doesn’t change.

Boyle’s Law

The pressure of a given mass of an ideal gas is inversely proportional to its volume at a constant temperature.

Gases have no?

Indefinite Shape.

Gas particles move?

Rapidly in all directions.

Gases have a very low?

Density

Gases are?

Compressible and are fluids.

Gas molecules are?

In a constant state of motion and frequently collide.

Pressure

The amount of force applied per unit of area.

Pressure’s Formula

Force/Area

When particles collide?

No energy is lost.

Deposition

Gas turning directly to a solid, skipping the liquid state.

Energy

Ability to do work.

Work

Ability to transfer energy.

Sources of Energy include?

Electricity, candles, batteries, and the food you eat.

Melting

To change matter from a solid to a liquid, thermal energy must be added.

Exothermic

Release of heat.

Endothermic

Absorption of heat.

Freezing

Process that is the reverse of melting.

Vaporization

Change of state of a liquid to a gas. There are two types of vaporization, boiling and evaporation.

Condensation

Change of a substance from a gas to a liquid.

Sublimation

Solid turns directly to a gas skipping the liquid state.

Temperature

Measure of average kinetic energy.

A change of state

The conversion of a substance from one physical form to another (Change of state is a physical change).

Heat

A transfer of energy.

Surface Tension

The tension of the surface film of a liquid caused by the attraction of the particles in the surface layer by the bulk of the liquid, which tends to minimize surface area.

Cohesion

Strong attractions between molecules.

Adhesion

Ability to stick to different molecules.

Viscosity

Friction on the flow of water.

High Viscosity

Moves Slower

Low Viscosity

Moves Faster

Vapor

The gas state of a substance that is normally a solid or a liquid at room temperature.

Plasma

State of matter that starts as a gas and then becomes Ionized.

Natural Plasmas are found in?

Lighting and fire.

Non-Natural Plasmas are found in?

Fluorescent light and neon signs.

Thermal Energy

Total potential and kinetic energy of an object.

Gas is matter that has?

No indefinite volume and no definite shape.

Modern Atomic Theory

What we think we know about atoms.

Aristotle’s theory

All matter is made of Air, Fire, Water, and Earth.

Democratis’s Theory

All matter is made of atoms.

Dalton’s Theory

Proved Democratis’s theory correct and Aristotle’s wrong.

Compounds

Combination of two or more different kinds of atoms.

John Dalton’s theory was the first theory that was scientifically accepted because?

He used evidence and new technology to actually prove his theory.

JJ Thompson

Worked with Cathode tubes and rays. He discovered electrons. He envisioned Plum pudding when looking into the cathode tube ray and tube so he called it Plum pudding.

Ernest Rutherford

Student of Thompson. Rutherford’s students expanded his own work placing an alpha particle source next to Gold foil. He is credited with discovering the Nucleus because he students only expanded his work.

James Chadwick

Was a colleague of Rutherford. Proposed that the Nucleus also contained neutral particles in Atoms called Neutrons.

Niels Bohr

Bohr’s model compares electrons to planets. Bohr suggested that electrons in an atom move in set paths around the Nucleus much like the planets orbit the sun in our Solar System. He also suggested that electrons can also be in certain energy levels.

An electron’s exact location?

Cannot be determined.

Quarks

Smaller parts that make up protons and neutrons.

It’s impossible to determine both the?

Exactly location of an electron in an atom and the electron’s speed and direction.

The best scientists can do is

Calculate the chance of finding an electron in a certain place within an atom.

SI Units

deci = 0.1

centi = 0.01

milli = 0.001

micro = 0.0000001

nano = 0.000000001

Length

A measure of the straight-line distance between two points.

Mass

A measure of the amount of matter in an object.

Volume

A measure of the size of a body or region in three-dimensional space.

Weight

A measure of the gravitational force exerted on an object.

Precision

The exactness of a measurement.

Accuracy

A description of how close a measurement is to the true value of the quantity measured.

Significant Figure

A prescribed decimal place that determines the amount of rounding off to be done based on the precision of the measurement.

Scientific tools scientists use

Computer Models

Physical Models

Telescopes Models

Microscopes

Controlled Experiment

Scientific investigation that tests one factor affects another.

Qualitive statement

Describes somethings with mathematical words.

Quantative statement

Describes something with mathematical questions.

Bar Graphs

Compare items

Pie Charts

Show parts of a whole

Two main classifications of matter

Substances and Mixtures.

Element

A substance that consists of just one type of atom: Elements are a substance that cannot be separated or broken down into simpler substances by Chemical means.

Compound

A substance made of atoms of two or more different elements that are chemically combined.

Chemical Formula

A combination of chemical symbols and numbers to represent a substance.

Mixture

Matter that can vary in composition. It’s combination of two or more substances that are not chemically combined.

Heterogenous Mixture

Type of mixture in which the individual substances are not evenly mixed.

Homogenous Mixture

Type of mixture in which the individual substances are evenly mixed.

Miscible

Able to mix well.

Immiscible

Not able to mix well.

Physical Properties

Shape

Mass

Volume

Density

Color

Size

Texture

Weight

State

Chemical properties

Rust

Change of Color

Something Burning

Digesting

Decomposing

Melting point

The temperature and pressure at which a solid becomes a liquid.

Boiling point

The temperature and pressure at which a liquid becomes a gas.

Density Formula

Mass/Volume

Useful Physical properties

Low Freezing Point

High Boiling Point

Water Resistance

Flexibility

Conductivity

Magnetic

State

The physical form in which a substance exists, such as a solid, liquid, and gas.

Chemical Change

A change that occurs when a substance changes composition by forming one or more new substances.

Flammability

Can catch on fire.

Reactivity

The ability of a substance to combine chemically with another substance.

All states of matter

Plasma, Liquid, Solid, Gas.

Solids

Are the most compact state of matter.

Gases

Are the least compact state of matter.

Plasma

The most common state of matter in the universe, but the least common state of matter on earth.

Amorphous Solids

Gum, Rubber, Glass.

Crystalline Solids

Diamond, Ice, Quarts.

Liquids

Can change shape, but not volume.

Surface Tension

The force acting at the surface of a liquid that causes a liquid, such as water, to form spherical drops.

Crystalline Solids

Have an orderly arrangement of atoms or molecules.