concept | definition |
First Law of Thermodynamics | conservation of energy and mass, energy is neither created nor destroyed |
heat | energy that flows from hotter to colder object |
temperature | property that determines the direction of heat flow |
combustion | combination of fuel and oxygen to form products |
exothermic reaction | term applied to any chemical or physical change accopanied by the the release of heat. |
Calorimeter | measures quantity of heat energy releaswed in a combustion reaction. ex: burning coal |
Endothermic reaction | any chemical or physical change that absorbs energy. ex: melting ice |
activation energy | energy necessary to initiate a reaction |
Tetraethyl lead substitues | 1) Ethanol 2) MTBE |
Entropy | randomness in position or energy level (going from order to disorder) Increase in entropy: exothermic. Decrease in entropy: endothermic |
second law of thermodynamics | energy is lost through heat |
Oil - refining process | crude oil (petroleum) refining process: crude oil separeted into fractions that consist of compounds with similar properties. |
Distillation | a purification, or separation, process in which a solution is heated to its boiling point and the vapors are condensed and collected. |
isomers | compounds with the same chemical formula but different chemical structure. ex. octane and isooctane |
Cracking | chemical process by which large moclecules are broken into smaller ones suitable to be used in gasoline |
thermal cracking | achieved by heating the starting materials to a high temperature |
catalytic cracking | catalysts are used to promote molecular breakdown at lower temperatures |
oxygenated gasolines | blends of petroleum-derived hydrocarbons with oxygen-containing compounds such as MTBE, ethanol or methanol |
Reformulated Gasolines | oxygenated gasolines that also contain a lower percentage of certain more volatile hydrocarbons such a benzene found in nonoxygenated conventional gasoline |
biomass | materials produced by biological processes |
refinery gases | Most volatile components of the fractionating tower boil far below room temperature |
hydrocarbons | molecules consisting of only hydrogen and carbon atoms |
Alkanes | hydrocarbons with only single bonds between carbons |
bond energy | the amount of energy that must be absorbed to break a specific chemical bond |
heat of combustion | quantity ofr heat energy given off when a specified amount of a substance burns in oxygen |
thermal energy | random motion of molecules |
potential and kinetic energy | potential: form of energy related to positions of atoms and molecular structure and stored in chemical bonds. kinetic: energy in motion |
calorie | amount of heat necessary to raise the temperature of exactly one gram of water by one degree Celsius. 4.184 J |
work | done when movement occurs against a restraining force. Work is equal to force multiplied by distance over which motion occurs |