jocelynn science Unit 2: Elements and Chemical Changes Test Review

Vocabulary and key concepts covering physical properties of metals, nonmetals, metalloids, rare earth elements, and evidence of chemical changes.

Element

A substance made of only one kind of atom that cannot be broken down into simpler substances.

Malleable

A material that can be hammered or bent into shapes without breaking.

Brittle

A material that breaks or shatters easily when force is applied.

Luster

How shiny or reflective a surface is.

Conductive

A material that lets heat or electricity pass through it easily.

Semiconductor

A material that can carry electricity sometimes, but not as well as a conductor.

Magnetic

A material that is attracted to magnets or can be made into a magnet.

Chemical Change

When a substance changes into a new substance with different properties.

Chemical Reaction

The process where substances interact and form one or more new substances.

Precipitate

A solid that forms and separates from a liquid during a chemical reaction.

Characteristics of Metal & Rare Earth Elements

Properties including solid state, malleable, ductile, high shiny luster, and good conductors of heat and electricity.

Characteristics of Nonmetals

Properties including existing as solids, liquids, or gas (most are gas at room temp), low dull luster, brittle, and good insulators.

Characteristics of Metalloids

Properties having characteristics of both metal and nonmetal; most have a shiny metallic luster like a metal but are brittle like a nonmetal, and act as semiconductors.

Periodic Table Element Categories

Classification showing Metals (Blue), Nonmetals (Green), Metalloids (Orange), and Rare Earth Elements (Yellow).

Evidence of Chemical Change

Production of Gas, precipitate, color change, change in thermal energy.

Physical Change Examples

Examples include glass shattering, chopping wood, tearing paper, iron melting, water turning red after adding red food coloring, mixing flour & water, blowing bubbles in milk, and cracking an egg.

Chemical Change Examples

Examples include two liquids mixing & forming a solid precipitate, wood burning, iron rusting, color forming when two clear liquids are mixed, mixing two substances & bubbles form, cooking eggs, a substance bursting into flames when exposed to oxygen, and a new smell appearing as something is cooking.