skibidi fuels Flashcards
What is a fuel?
Fuels are dense repositories of energy consumed to provide energy services such as heating, transportation, and electrical generation.
Fuels produce energy in the form of heat through combustion.
What are the different classifications of fuel?
- Solid fuels
- Liquid fuels
- Gaseous fuels
Each classification has unique characteristics and examples.
What are some examples of solid fuels?
- Coal
- Coke
- Coal char
- Peat
- Wood
- Solid wastes and biomass
Solid fuels are characterized by their physical state and combustion properties.
What are some examples of liquid fuels?
- Liquid petroleum fuels
- Non-petroleum liquid fuels
- Tar sands
- Oil shale
- Coal-derived fuels
Liquid fuels are derived from various sources and processed differently.
What are some examples of gaseous fuels?
- Natural gas
- Hydrogen gas
- Acetylene
- Miscellaneous fuels (e.g., producer gas, coal gas)
Gaseous fuels are often used for heating and power generation.
How do fuels generate energy?
Fuels release energy through the combustion process, involving the breaking and forming of chemical bonds.
Energy is stored when bonds absorb energy and released when bonds are formed.
What happens during the combustion of a fuel?
Energy released is equivalent to the difference in energy between broken and formed bonds.
The process involves breaking C-H and O-O bonds and forming C-O and H-O bonds.
What is the compression ratio in an internal combustion engine?
The ratio of the maximum volume of the gasoline-air mixture at the beginning of the compression stroke to the volume of the fully compressed mixture.
A higher compression ratio leads to more power and energy extraction from fuel.
What is knocking in an internal combustion engine?
Knocking is a rapid pinging sound resulting from premature ignition of the fuel-air mixture.
It leads to loss of power and can cause engine damage.
How does octane number relate to engine performance?
Higher octane numbers indicate a fuel’s ability to resist knocking, improving engine performance.
Branched alkanes have higher octane ratings due to their smooth combustion.
What is the significance of octane (C8H18) in fuel?
Octane is a reference hydrocarbon used to evaluate octane ratings, assigned a value of 100 for its resistance to knocking.
Heptane, with a tendency to knock, is assigned a value of 0.
What is calorific value?
The amount of heat liberated from the complete combustion of fuel.
Higher calorific values indicate more energy released during combustion.
How can the calorific value of a fuel be determined?
Using the method of calorimetry, applying the First Law of Thermodynamics.
This law states that energy cannot be created or destroyed.
What does the First Law of Thermodynamics state?
Energy can neither be created nor destroyed.
It is foundational in understanding energy transformations in fuels.
What is the Second Law of Thermodynamics?
The entropy of the universe is increasing.
This law relates to the transformation of thermal energy into ordered work.
