Fire / Science Homework
tinkme07
unit_4_fire_and_science.docx1. What terms are used to describe the tendency of materials to become solutions?
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Miscibility and mixtures |
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Solubility and mixtures |
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Miscibility and solubility |
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Solutions and mixtures |
7 points
Question 2
1. Which metals are highly reactive with water?
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Alkali metals |
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Metalloids |
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Alkaline metals |
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Transition metals |
7 points
Question 3
1. What must be overcome for vapors to escape surface tension?
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Vapor pressure |
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Atmospheric pressure |
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Head pressure |
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Boiling point |
7 points
Question 4
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when heat transfers downward through fuel to water in the tank's bottom, which in turn is raised to its boiling point. |
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as water sinks below the fuel surface, and heated fuel causes water to boil, resulting in frothing bubbles of ignitable liquid which burn easily. |
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when expansion at upper regions of the fuel expands sufficiently to cause fuel to eject from the tank. |
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when a combustible liquid has a surface fire being fought with water or foam and it sinks below the fuel surface. |
7 points
Question 5
1. Which of the following is NOT a property associated with thermal inertia?
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Density |
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Specific heat |
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Thermal conductivity |
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Ignition temperature |
7 points
Question 6
1. Orientation of the fuel refers to:
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horizontal, vertical, or inclined plane exposure to flame. |
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proximity to the ignition source. |
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location within the compartment of origin. |
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the surface experiencing radiant heating. |
Question 7
1. Which of the following best defines surface-to-mass ratio?
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Increased mass, with lessening of the surface area. |
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Increased surface area compared to lessening of the mass. |
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The surface area in relation to the total mass of an object. |
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Decreased mass with increased surface area. |
Question 8
1. A dust explosion can occur when what conditions are met?
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Dusts are suspended in the air. |
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Concentration of fuel is within its flammable limits. |
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Dust is visible in the air. |
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The fuel is raised to ignition temperature and spreads throughout. |
Question 9
1. What term describes a solid that absorbs heat energy readily and does not transfer it as quickly through the material to the opposite side?
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Thermally thin |
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Thermally thick |
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Thermal inertia |
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Surface-to-mass ratio |
Question 10
1. Heat release rates of fires involving burning liquids are derived from which of the following variables?
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Potential barriers and unexposed surface areas |
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Potential energy and unexposed surface areas |
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Potential energy and exposed surface areas |
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Potential barriers and exposed surface areas |
Question 11
1. List the different types of solid fuels and describe their fuel characteristics. Your response should be at least 75 words in length
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Question 12
1. What are the variables affecting solid combustion? Briefly describe each one. Your response should be at least 75 words in length.
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Question 13
1. A 50 gallon tank of methanol failed and the contents spilled on the ground. The size of the spill covered 10 square meters. If this spill should ignite, what would be the heat release rate of the fire? Note for methanol: = 22 (g/m2-s) and ΔHc [JM1] = 20,000 kJ/kg Your answer should show your calculations and your answer must include the proper units
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