5 - Gasses Flashcards
What is Pressure?
Pressure is force per unit of area. It is expressed in pounds per square inch
FORMULA: p = F / A
What is Pascal’s Law?
Pascal’s law states that pressure applied upon a confined fluid is transmitted equally and undiminished in all directions. (Fluids include both liquids and gases)
What is the heat of compression?
As a gas is compressed into a smaller volume, its pressure and temperature rise. This is due to the work (energy) added to the gas by compression. The energy added is termed the heat of compression.
How is evacuation related to the relation between pressure and temperature changes?
When pulling a vacuum on a refrigeration circuit, the temperature at which water vaporizes is significantly lowered, allowing trapped liquid water to vaporize and be drawn out of the circuit.
What happens to a substance temperature wise when pressure is increased?
The temperature at which a phase change will occur will increase as well.
What is critical temperature?
What is critical pressure?
The critical temperature of a substance is the highest temperature at which a substance may be liquified, regardless of the pressure applied to it.
Ex: Water’s critical temperature is 705F. No matter how much the pressure is lowered, it cannot be converted back to a liquid once it exceeds this temperature.
The critical pressure of a substance is the pressure at which the gaseous form of a substance liquefies when the substance is at its critical temperature. When a gas is at its critical temperature, any pressure less than the critical pressure causes the substance to remain in gaseous form.
What is a monometer, and what method of pressure measurement does it use?
A monometer is designed for measuring small pressures above or below atmospheric pressure. They are calibrated in inches of water column.
What is a compound gauge?
A gauge that a technician can use to measure above and below atmospheric pressure
What is Boyle’s Law?
Boyle’s law states that the volume of a gas varies inversely to the pressure, provided the temperature remains constant.
What is Charles’ Law?
Charles’ Law states that with a constant pressure, the volume of a given quantity of gas varies directly to the absolute temperature.
What is Gay-Lussac’s Law?
Gay-Lussac’s law states that at constant volume, the absolute pressure of a given quantity of a gas varies directly with its absolute temperature. When a gas is held at a constant volume, its pressure and temperature will rise together or will fall together.
What is the combined gas law?
The combined gas law states that the ratio among a gas’s pressure, volume, and temperature remain constant. If a gas’s temperature increases, its pressure or volume must increase proportionally.
FORMULA: k = (P X V)/T
What is Avogadro’s Law?
Avogadro’s Law states that equal volumes of gases at equal pressures and temperatures contain equal numbers of molecules, regardless of the mass of the gases.
What is Dalton’s Law?
Dalton’s Law states that to determine the total pressure of a confined mixture of gases, the pressure for each gas involved must be added.
What is saturated vapor?
The term saturated vapor indicates a condition of balance on an enclosed quantity of a vaporized fluid. The balance is such that some vapor will condense if there is even the slightest lowering of its temperature or an increase in pressure.
