Untitled Flashcard Set (copy)

Atomic Number (Z)

The number of protons in an atom, which defines the element.

Atomic Mass

The weighted average of the masses of an element's isotopes.

Metals

Elements that are generally good conductors of heat and electricity, malleable, and ductile.

Nonmetals

Elements that are generally poor conductors of heat and electricity, often brittle.

Metalloids (Semimetals)

Elements that have properties intermediate between metals and nonmetals.

Pure Substance

A substance with a uniform and definite composition.

Element

A pure substance consisting of only one type of atom.

Compound

A pure substance formed when two or more different elements are chemically bonded together.

Physical Change

A change in form or appearance but not in chemical composition.

Chemical Change

A change where a new substance with different chemical properties is formed.

Significant Figures

Digits in a number that contribute to its precision.

Isotopes

Atoms of the same element that have different numbers of neutrons.

Average Atomic Mass

The weighted average mass of all naturally occurring isotopes of an element.

Scientific Method

A systematic process for conducting scientific research.

Observation

The act of noticing a phenomenon or problem.

Hypothesis

A testable explanation or prediction for an observation.

Experimentation

The process of designing and conducting tests to prove or disprove the hypothesis.

Conclusion

The determination of whether the hypothesis was supported or rejected.

Metric Units

Standard measurements used in scientific contexts, such as meters and grams.

Dimensional Analysis

A method of converting units using conversion factors.

Chemical Symbol

A notation representing a chemical element.