Source of Energy

solar cell:a device that generates an electric current from sunlight.



biomass: conversion:getting energy from plant and animals material by changing them into high quality fuels.



nuclear fission: fission: the spliting of a nucleus with a large mass into two nuclei with smaller masses.



change reaction:a reaction that is kept going by products of the reaction.





nuclear fusion:the merging of nuclei with smaller masses into a nucleus with a large mass.

 


hydroelectric:the use of flowing water to generate electricity.


thermal pollution: the excess heating of the inviroment.

Temperature,Heat,and Matter

thermal expansion:the expansion of matter when its temperature is rased.




pressure:the force on each unit of area ofa surface.



melting;the change into a solid to liquid.´


 

vaporization: the change into a liquid to a gas as a molecule atrac each other.



condensation:the change of a gas into a liquid as the molecule attract each other.

freezing:the change into a liquid to a gas.

boiling: the formation of bubbles of vapor that escape from a liquid that is beging heated.

Temperature and Heat

Kinetic energy: the energy of a moving object.







Potential energy: energy storedin an object of materials.





Temperature: the average kinetic energy of the molecules in a materials.







heat:energy that flows between objects that have differents temperatures.







Radiations: The transfer of enrgy by elecromangnetic waves.







conduction:the transfer of energy by the flow ofa liquid or gas.







Convection:the transfer of energy by the flow of a liquid or gas.







Insulation: prevents heat from flowing in out of a materials.

Chemical Properties

compund : a chemical combination of two or more elements.




chemical bond : a link that aoms or electrical charge particles can forms with each others.



chemical formual :  a way of using letters an nubers to show how much of each element is in a substance.




ion : an electrical charge particle with unequal numbers of protons and electrons.




molecule : a group of abandoned atoms act like a single particle.






chemical properties : a way of discribing how a substance change chemicaly with other substance.




exothermic : a reaction that give the heat.




endothermic : a reactuion that absorbed heat.