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.

 

Element and Atom

Element:a substance that cannot be broken down any futher into anything simpler.

Atom:the smallest particlee of an element that has the same chemical properties as the element.

Nucleus:an atom"s dense center, where most it mass is.

Electron:a negatively charge particle that move araund an atoms nucleus.



Proton:a posotively charge particle inside an atom nucleus.




Neutron:a particle with no charge inside an atom nucleous.´




Atomic: Number:the nbunber of protons in an atom.´



Metal:any of a grup of element  that conduct head an electricity is shiny an bendable.

Phisical Properties.

Matter:any solid,liquid,or,gas.

Mass:the amaunt os space an object take up.

Volume:the amaunt os sapce an object takes up.

Density:The amaunt of mass in a certain volume of material.

Physical Properties:a property can be observe without changin the identtify of a substance.

Physical Change:a change in saize,shape,or sate without forming a new substance.

Solution:a mixture of one substance dissolved in another so that  the properties are the same throught.

Chemical Change:a change in matter that producers a new substance with different properties from the original.

1:Mass:balance (g) 1000=1 kg

2:Volume: liquid,solid =graduated liquid cylinder and solids graduated ruler (m3)

3:Density:mass,volume (g) m3 = G/m3

iron 500 C
water 100 C
blood 40 C

Mass:a measure of how hard it is to push or pull an object.

Phisical change
1.size.
2.shape.
3.state.
4.mixture.

Chemical Change

1.fermentation.
2.combustion (burning)
3.change in color