jueves, 28 de abril de 2011

Vocabulary #6

1.Solar Cell: A device that generates an electric current on sunlight.


2.Biomass Convenction: Getting energy from plants and animals materials by changing them into high qualities fuel.


3. Nuclear Fission: The splitting of a nucleus with a large mass into two nuclei with smaller masses.


4.Chain Reaction: A reaction that is kept going by product of their reaction.

5.Nuclear Fusion: The merging of nuclei with smaller masses into nucleus with a larger mass.


6.Hidroelectricity: The use of flowing water to generate electricity.


7.Thermal Pollution: The excess heating of the environment.

lunes, 25 de abril de 2011

Vocabulary #5

1.Thermal expansion: The expansion of matter when its temperature is raised.

Pressure: The force on each unit of area of a surface.

3.Melting: The change of a solid into a liquid.


4.Vaporization: The change of a liquid to a gas as molecules break free from each other.

5.Condensation: The change of a gas to a liquid as molecules break free from each other.

6.Freezing: The change of a liquid into a solid.

7. Boiling: The formation of bubbles of vapor that escape from a liquid that is being heated.



8. Evaporation: The vaporization of molecules from the surface of a liquid.

Vocabulary #4

1.Kinetic energy: The energy of a moving object.


2.Potential energy: Energy stored in an object.

3.Temperature: The average kinetic energy of the molecules in a material.


4.Heat: Energy that flows between objects that have different temperatures.


5.Radiation: The transfer of energy by electromagnetic waves.


6.Conduction: The transfer of energy by the flow of a liquid or gas.

7.Insulation: Prevents heat from flowing in or out of a material.


Vocabulary #3

1.Compound: A chemical combination of two or more elements.

2.Chemicl bond: A link that atoms or electrically charged particles can form with each other.

3.Chemical formula: A way of ussing letters and numbers to show how much of each element is in a substance.

4.Ion: An elecrically charged particle with unequal numbers of protons and electrons.

5.Molecule: A group of bonded atoms that act like a single particle.

6.Chemical property: A way of describing how a substance changes chemically with other substances.

7.Exothermic: A reaction that gives off heat.


8.Endothermic: A reaction that absorbs heat.

Vocabulary #2

1.Element: A substance that cannot be broken down any further into anything simpler.


2.Atom:The smallest particle of an element that has the same chemicla properties as the element.


3.Nucleus: An atom"s dense center,where most of it"s mass is.



4.Electron: A negatively charged particle that moves around an atom"s nucleus.






5.Proton: A positively charged particle inside an atom"s nucleus.


6.Neutron: A particle with no charge inside an atom"s nucleus.




7.Atomic Number: The number of protons in an atom.





8.Metal: Any of a group of elements that conduct heat and electricity,is shiny and bendable.