1.0 1.0 Scientific Method

Observe

To watch carefully in order to gain information.

Identify

To recognize or find something.

Research

To investigate and study materials in order to discover facts and reach new conclusions.

Hypothesis

A possible answer or educated guess to a scientific question.

Test

To conduct an experiment to determine the validity of a hypothesis.

Observe and Analyze

To carefully examine and break down data or results.

Draw conclusion

To make decisions or judgments based on analyzed data.

Report

To present findings from an experiment or research.

Variables

Elements that can change during an experiment.

Independent Variable

The variable that is controlled or manipulated in an experiment.

Dependent Variable

The variable that responds or changes as a result of the independent variable.

Controlled Variable

Factors that remain constant throughout an experiment.

Trials

Runs of an experiment that should be conducted multiple times to ensure accuracy.

Qualitative Observation

Observation that does not involve measurements or numbers.

Quantitative Observation

Observation that involves numerical measurements.

Graph

A visual representation that shows patterns in data.

Matter

Anything that has mass and occupies space.

Particle Theory of Matter

A theory that describes how matter is composed of tiny particles and their behavior.

Pure substances

Materials made up of only one type of particle.

Element

A pure substance that cannot be broken down into simpler substances.

Compound

A substance made up of two or more different elements in a fixed proportion.

Mixtures

Substances made up of two or more different types of particles.

Mechanical Mixtures

Mixtures where different components can be seen.

Solutions

Uniform mixtures of two or more substances.

Physical Properties

Characteristics observed using the senses.

Luster

The shine or dullness of a substance.

Optical Clarity

The ability of a substance to allow light to pass through.

Brittleness

The tendency of a substance to break easily.

Viscosity

The ability of a substance to flow or pour.

Hardness

The ability of a substance to resist scratching.

Malleability

The ability of a substance to be hammered into thin sheets.

Ductility

The ability of a substance to be drawn into a thin strand.

Electrical Conductivity

The ability of a substance to conduct an electric current.

Physical Change

A change that does not alter the composition of a substance.

Chemical Properties

Characteristics that describe how a substance reacts to form new substances.

Chemical Changes

Changes that result in the formation of new substances.

Clues of Chemical Change

Indicators such as color change, gas formation, or temperature change.

Density

The mass of a substance divided by its volume.

Melting Point

The temperature at which a solid becomes a liquid.

Boiling Point

The temperature at which a liquid turns into vapor.

Atomic Theory

The scientific theory that all matter is composed of atoms.

Democritus

Ancient philosopher who proposed that all matter is made of indivisible particles called atoms.

John Dalton

Developed the first atomic theory proposing atoms are indivisible and indestructible.

J.J. Thomson

Discovered the electron and proposed the 'plum pudding' model of the atom.

Ernest Rutherford

Discovered the atomic nucleus through the Gold Foil Experiment.

James Chadwick

Discovered the neutron, contributing to atomic structure understanding.

Niels Bohr

Proposed the Bohr model of the atom with quantized electron orbits.

Atomic Number

The number of protons in an atom's nucleus.

Mass Number

The total number of protons and neutrons in an atom's nucleus.

Isotopes

Atoms with the same number of protons but different numbers of neutrons.

Chemical Formula

A notation that shows the types and numbers of atoms in a substance.

Molecular Compound

A compound consisting of two or more non-metal atoms.

Ionic Compounds

Compounds formed between metals and non-metals.

ION

An atom that has lost or gained electrons, resulting in a charged particle.

Stability

The tendency of atoms to bond and achieve a full valence shell.

Ionic Bond

Bond formed when atoms lose or gain electrons.

Covalent Bond

Bond formed by the sharing of electrons between non-metal atoms.

What did Democritus propose about atoms?

Democritus proposed that everything is made of tiny, indivisible particles called atoms, suggesting they are the basic building blocks of matter.

What is John Dalton known for in atomic theory?

John Dalton developed the first atomic theory, suggesting that all matter is made of indivisible and indestructible atoms.

What discovery is J.J. Thomson credited with in atomic science?

J.J. Thomson is credited with the discovery of the electron in 1897 through cathode ray experiments.

What was the primary conclusion of Ernest Rutherford's Gold Foil Experiment?

Ernest Rutherford's Gold Foil Experiment concluded that an atom is mostly empty space with a dense, positively charged nucleus at its center.

What significant particle did James Chadwick discover?

James Chadwick discovered the neutron in 1932, enriching the understanding of the atomic nucleus.

What key concept did Niels Bohr introduce in his model of the atom?

Niels Bohr proposed that electrons orbit the nucleus in fixed paths (quantized orbits) and that the energy levels of these orbits can vary.

What are protons, electrons, and neutrons collectively known as?

Protons, electrons, and neutrons are collectively known as PEN, which are the fundamental particles of an atom.

What are the Steps?

Observe, Identify, Research, Hypothesis, Test, Observe and Analyze, Draw conclusion, and Report