IFSTA 7th Edition Chapter 4: Fire Dynamics Questions and Correct Answers (Graded A)
True or False: Oxidizers affect a fire because they are combustible - ANSWER-False. Oxidizers are not combustible but will support or enhance combustion
Physical science is the study of what two things? - ANSWER-Matter and energy
Oxidation - ANSWER-A chemical reaction involving the combination of an oxidizer, such
as oxygen in the air, with other materials.
Energy - ANSWER-The capacity to perform work
Work - ANSWER-This occurs when a force is applied to an object over a distance or when a substance undergoes a chemical, biological, or physical change. In the case of heat, work means increasing a substance's temperature
Potential Energy - ANSWER-The amount of energy that an object can release at some point in the future. Stored energy
Heat of Combustion - ANSWER-The potential energy available for release in the combustion process
Kinetic Energy - ANSWER-The energy that a moving object possesses
What are the 7 types of energy? - ANSWER-Chemical
Thermal
Mechanical
Electrical
Light
Nuclear
Sound
How is energy measured in the International System of Units (SI)? - ANSWER-With joules
How many joules is required to change the temperature of 1 gram of water by 1 degree Celsius? - ANSWER-4.2J In the customary system, the unit of measurement for heat is what? - ANSWER-The British Thermal Unit (Btu)
What is the British thermal unit? - ANSWER-The amount of heat required to raise the temperature of 1 pound of water by 1 degree Fahrenheit
1 Btu equals how many joules? - ANSWER-1055 J
Exothermic Reactions - ANSWER-Reactions that emit energy as they occur
Endothermic Reactions - ANSWER-Reactions that absorb energy as they occur
What are the 3 elements to the Fire Triangle? - ANSWER-Fuel, Oxygen, Heat
What are the 4 elements to the Fire Tetrahedron? - ANSWER-Reducing Agent (Fuel), Oxidizing Agent, Heat, Chemical Chain Reaction
Pyrolysis - ANSWER-Off-gassing of a solid
Vaporization - ANSWER-Off-gassing off liquids
True or False: Both pyrolysis and vaporization are chemical changes - ANSWER-False. Pyrolysis is a chemical change from a solid to a gas, but vaporization is a physical change from a liquid to a gas
Piloted Ignition - ANSWER-The most common form of ignition. Occurs when a mixture of fuel and oxygen encounter an external heat source to ignite
Autoignition - ANSWER-Occurs without any external flame or spark to ignite the fuel gases or vapors
Autoignition temperature - ANSWER-The minimum temperature at which a fuel in the air must be heated in order to start self sustained combustion
True or False: The autoignition temperature of a substance is always higher than its piloted ignition temperature - ANSWER-True
Entrainment - ANSWER-The drawing in and transporting of solid particles or gases by the flow of a fluid
True or False: Smoke is a product of incomplete combustion - ANSWER-True
What does incomplete combustion mean? - ANSWER-Some of the fuel does not burn, but instead gets entrained with hot gases and rises aloft. This unburned fuel is smoke, and it has the potential to burn
True or False: Oxidizers affect a fire because they are combustible - ANSWER-False. Oxidizers are not combustible but will support or enhance combustion
Physical science is the study of what two things? - ANSWER-Matter and energy
Oxidation - ANSWER-A chemical reaction involving the combination of an oxidizer, such
as oxygen in the air, with other materials.
Energy - ANSWER-The capacity to perform work
Work - ANSWER-This occurs when a force is applied to an object over a distance or when a substance undergoes a chemical, biological, or physical change. In the case of heat, work means increasing a substance's temperature
Potential Energy - ANSWER-The amount of energy that an object can release at some point in the future. Stored energy
Heat of Combustion - ANSWER-The potential energy available for release in the combustion process
Kinetic Energy - ANSWER-The energy that a moving object possesses
What are the 7 types of energy? - ANSWER-Chemical
Thermal
Mechanical
Electrical
Light
Nuclear
Sound
How is energy measured in the International System of Units (SI)? - ANSWER-With joules
How many joules is required to change the temperature of 1 gram of water by 1 degree Celsius? - ANSWER-4.2J In the customary system, the unit of measurement for heat is what? - ANSWER-The British Thermal Unit (Btu)
What is the British thermal unit? - ANSWER-The amount of heat required to raise the temperature of 1 pound of water by 1 degree Fahrenheit
1 Btu equals how many joules? - ANSWER-1055 J
Exothermic Reactions - ANSWER-Reactions that emit energy as they occur
Endothermic Reactions - ANSWER-Reactions that absorb energy as they occur
What are the 3 elements to the Fire Triangle? - ANSWER-Fuel, Oxygen, Heat
What are the 4 elements to the Fire Tetrahedron? - ANSWER-Reducing Agent (Fuel), Oxidizing Agent, Heat, Chemical Chain Reaction
Pyrolysis - ANSWER-Off-gassing of a solid
Vaporization - ANSWER-Off-gassing off liquids
True or False: Both pyrolysis and vaporization are chemical changes - ANSWER-False. Pyrolysis is a chemical change from a solid to a gas, but vaporization is a physical change from a liquid to a gas
Piloted Ignition - ANSWER-The most common form of ignition. Occurs when a mixture of fuel and oxygen encounter an external heat source to ignite
Autoignition - ANSWER-Occurs without any external flame or spark to ignite the fuel gases or vapors
Autoignition temperature - ANSWER-The minimum temperature at which a fuel in the air must be heated in order to start self sustained combustion
True or False: The autoignition temperature of a substance is always higher than its piloted ignition temperature - ANSWER-True
Entrainment - ANSWER-The drawing in and transporting of solid particles or gases by the flow of a fluid
True or False: Smoke is a product of incomplete combustion - ANSWER-True
What does incomplete combustion mean? - ANSWER-Some of the fuel does not burn, but instead gets entrained with hot gases and rises aloft. This unburned fuel is smoke, and it has the potential to burn
