7th Grade

Unit 11: Chemical Reactions and Compounds

Lesson 1: Physical Properties of Elements

Vocabulary of Instruction:

1. Brittle• Having little elasticity; hence easily

cracked, fractured, or snapped.

2. Conductivity• Property of metals and alloys that allows

heat or electrical charges to pass through the material easily.

3. Ductile• Ability of metals to be drawn into wires.

4. Luster• Property of metals and alloys that describes

having a shiny appearance or reflecting light.

5. Magnetic• The properties and interactions of

magnets to attract other metal objects.

6. Malleable• Ability of metals and alloys to be rolled or

hammered into thin sheets.

7. Metal• Element that typically is a hard, shiny solid, is

malleable, and is a good conductor of heat and electricity.

8. Metalloid• Element that shares some properties with

metals and some with nonmetals.

9. Nonmetal• Element that usually is a gas or brittle solid at

room temperature, is not malleable or ductile, is a poor conductor of heat and electricity, and typically is not shiny.

10. Reactive• A chemical that, in the pure state, or as

produced or transported, will vigorously polymerize, decompose, condense, or become self-reactive under conditions of shock, high pressure, or high temperature.

11. Semiconductor• Materials having conductivity properties

between that of metals (good conductors) and nonmetals (insulators) and having controllable conductivity parameters.

Silicon Germanium

12. Sonorous• Capable of giving out a deep, resonant

sound.