Question | Answer |
Chemistry | the study of substances and the changes they undergo |
central science | overlaps all other sci |
energy | the capacity to do work |
work | the capacity to move an obj. over a distance against a resisting force |
forms of energy | kinetic, radiant, and potential |
KE | energy of motion |
mechanical energy | KE |
thermal energy | KE |
random internal motion of particles | KE |
radiant | energy from sun |
potential | stored energy |
energy possessed by object because of position or arrangement of particles | PE |
measurement of energy | calorie or joule |
1 cal = | 4.184 J |
law of conserv. of energy | in any process, energy is neither created nor destroyed |
fossil fuels | coal and petroleum and natural gas |
measurement of temp. | celcius and farenheit |
kelvin scale | SI unit of temp. (K) |
c=k-? | 273 |
absolute zero | point at which the motion of particles of matter ceases |
matter | anything that has mass and volume |
states of matter | solid liquid gas plasma |
chemical changes alter | the identity of a substance |
physical changes alter | looks but not identity |
type of change where new substance is created with new properties | chemical change |
sodium | Na |
Copper | Cu |
Lead | Pb |
Tungsten | W |
Iron | Fe |
Tin | Sn |
Potassium | K |
gold | Au |
Mercury | Hg |
SIlver | Ag |
------- can not be separated by physical or chemical means | element |
elements are abbreviated with | symbols and letters |
elements are organized on the | periodic table |
compound | two or more elements chemically combined |
pure substances | elements and compounds- because they have a unique set of chemical and physical properties |
specific heat capacity formula | H= mc (delta) t |
gasoline in car is ex. of ? energy | potential |
mixture | substances that have come together but are not chemically combined |
homogeneous | undistinguishable |
heterogeneous | distinguishable |
ways of seperation | evaporation, crystallization, distilling, filtering, chromotog., centrifuge |
heterogeneous mix. often seperated by | filtration |
seperating sand and water can be done by | filtration |
separating sugar from sugar water by | crystallization |
separation that takes advantage of boiling points is | distillation |
removing chlorophyll form leaves by | chromo. |
decompose water into h and o by | electrolysis |
crude oil into gas | distillation |
magnesium + oxygen | magnesium oxide |
iron + sulfur | iron II sulfide |