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Boy's gas calorimeter
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### Boyle report

1. boyle Report Lab Khogr kamal Ibarhim Second Class Production and metallurgy engineering 2018-2017
2. Experiment No:- 1 Experiment Name :-Boyle's law & lussa's law Objective:- 1- Demonstrating the laws of state changes in gasses experimentally 2- Isothermal change of state ,Boyle's law . 3- Isochoric change of state ,gay lussa's law History of boyle's law:- Boyle's law (sometimes referred to as the Boyle–Mariotte law, or Mariotte's law[1] ) is an experimental gas lawthat describes how the pressure of a gas tends to increase as the volume of the container decreases. A modern statement of Boyle's law is The absolute pressure exerted by a given mass of an ideal gas is inversely proportional to the volume it occupies if the temperature and amount of gas remain unchanged within a closed system. Mathematically, Boyle's law can be stated asor where P is the pressure of the gas, V is the volume of the gas, and k is a constant. The equation states that product of pressure and volume is a constant for a given mass of confined gas as long as the temperature is constant. For comparing the same substance under two different sets of conditions, the law can be usefully expressed as The equation shows that, as volume increases, the pressure of the gas decreases in proportion. Similarly, as volume decreases, the pressure of the gas increases. The law was named after chemist and physicist Robert Boyle, who published the original law in 1662. Objective:- The objective of this experiment is to study the relationship between the pressure and volume of an air sample at constant temperature. This will be done by measuring the pressure of a constant amount of air contained in a cylinder as the volume of the air is varied. The results will be compared with the predictions of Boyle’s law and the ideal gas law
3. THEORY Boyle’s law:- states that, for constant temperature, the product of the volume and the pressure of an ideal gas is a constant. The ideal gas law PV = C PV = nRT ( states that this constant (nRT) is proportional to the amount of ideal gas in the sample (the number of moles, n) and the absolute temperature, T. The constant R in this equation is the universal gas constant which has a value of R = 8.31 J/(mole.K) in SI units. Note that if T is held constant throughout the experiment, then the ideal gas law reduces to Boyle’s law Method: switch on unit master switch (4) open the air discharge valve (1) on the lid of the cylinder place both 3-way valves (3) in position 2 switch on compressor using switch until the liquid level has reached the lowest mark (2) on the scale on the vessel. switch off compressor close discharge valve on the lid of the cylinder! start data acquisition program and make the corresponding settings switch on compressor at the latest at liter residual volume for the air enclosed ,switch off the compressor open graph measured valued and interpret leave pressure cylinder uncharged and continue immediately with the compression experiment
4. EQUIPMENT and COMPONENTS USED:- 1) Tank 1 for isothermal change of state, (2) Digital displays, (3) 5/2-way valve for switching between compression and expansion, (4) Heating controller, (5) Digital display, (6) Tank 2 for isochoric change of state
5. MORE EXAMPLES OF BOYLE'S LAW As long as the temperature and number of moles of a gas remain constant, Boyle's law means doubling the pressure of a gas halves its volume. Here are more examples of Boyle's law in action:  When the plunger on a sealed syringe is pushed, the pressure increases and the volume decreases. Since boiling point is dependent on pressure, you can use Boyle's law and a syringe to make water boil at room temperature.  Deep sea fish die when they are brought from the depths up to the surface. The pressure decreases dramatically as they are raised, increasing the volume of gases in their blood and swim bladder. Essentially, the fish pop!  The same principle applies to divers when they get "the bends." If a diver returns to the surface too quickly, dissolved gases in the blood expand and form bubbles, which can get stuck in capillaries and organs.  If you blow bubbles underwater, they expand as they rise to the surface. One theory about why ships disappear in the Bermuda Triangle relates to Boyle's law. Gases released from the sea floor rise and expand so much that they essentially become a gigantic bubble by the time they reach the surface. Small boats fall into the "holes" and are engulfed by the sea.
6. GAY LUSSAC LAW:- Introduction: When you have a can of soda or beer, and you heat it too much by leaving it in your car or out in the sunlight for too long a period of time, you may find an unpleasant surprise when you return to fetch it, as people have found out here and here. The amount of liquid in the can hasn't grown. Instead, the carbon dioxide inside has been agitated thermally, thus increasing the pressure, and you then have to deal with the messy results of container bursting due to this increase in kinetic energy. Inconvenient incidences of pressurized containers exploding when they are heated may be explained by the Law of Gay-Lussac. Gay-Lussac's Law is the third and final of the laws leading up to the ideal gas law. The first is Boyle's Law, which gives the relationship between volume and pressure, and the second is Charles' Law, which gives the relationship between volume and temperature. Gay-Lussac's Law has also been referred to as Charles' Law, but they are not the same OBJECTIVES: The aim of this experiment is to determine the relationship between pressure and temperature at constant volume of an ideal gas. THEORY: Gay-Lussac law is also commonly known as Charles’s law. The law explains about the relationship between pressure and temperature of gases. The law was established in theearly19thcentury by Jacques Charles and Joseph Louis Gay-Lussac who did a study on the effect of temperature on the volume of a sample of gas subjected to constant pressure (Atkins, 2002). Charles did the original work, which was then verified by Gay-Lussac (grc.nasa.gov).However, in this lab practical, we are dealing with an alternative version of Charles's law instead. The volume is kept constant in change for pressure instead as the objective of the experiment is to determine the relationship between pressure and temperature of ideal gas. The expression is as shown = constant x T (at constant volume) This version of law also indicates that the pressure of gas falls to zero as the temperature is reduced to zero (Atkins, 2002). Thus it can be seen that gas pressure and the temperature are directly proportional tone another. When the pressure increases, the temperature also increases, and vice versa.
7. P ∝T P = constant T P/T = constant P1/T1= P2/T2 P1T2= P2T1 The equations above apply in the gas of dealing with therelationship between pressure and temperature of a gasMathematical/Graphical relationship between pressureof a fixed mass of gas with temperature at a constantvolume is linear. The vo lume is constant. Method: Heating: 1.switch on unit at master switch. 2.open air discharge valve on the lid of the heatable cylinder and set the vessel to ambient pressure . 3.close air discharge valve again. 4.set the required final temperature on the heating regulator using the arrow keys 5.start data acquisition program and make the corresponding settings. 6.switch on heater and operate as long as necessary until the final temperature is reached. 7.open graph of measured values and interpret. 8. leave the cylinder unchanged and continue immediately with the cooling experiment . Cooling 1.switch off heated 2.open air discharge valve on the lid of the heatable cylinder and set the vessel to ambient pressure. 3.close air discharge valve again. 4. start data acquisition program and make the corresponding settings. 5.leave the vessel to cool to ambient temperature . 6. open graph of measured values and interpret. 7.open air discharge valve on the lid of the cylinder and set the vessel to ambient pressure . 8.switch off unit at master switch.
8. EQUIPMENT & COMPONENTS USED: (1) Tank 1 for isothermal change of state, (2) Digital displays, (3) 5/2-way valve for switching between compression and expansion, (4) Heating controller, (5) Digital display, (6) Tank 2 for isochoric change of state (7) Red switch to on and off the machine{ Applications 1) Car tires in hot weather: Usually hot tires tend to explode in hot weather because hot weather means more temperature which will let the pressure increase also because they are directly proportional as Gay Lussac imposed. By increasing temperature of the system we increase the pressure of the gas. So when the pressure of the gas exceeds the elastic capability of the tire, the tire explodes. This Phenomena expresses Gay Lusaac's Law of Temperature and Pressure. 2) an aerosol can is another example because if it is exposed into a flame , the temperature will increase so the pressure will too. b the time, the pressure would build up causin the can to explode. it's a real proof for Gay Lussac's law as it describes the relation between temperature and pressure. Moreover, there are warnings on these cans because of that. 3) Pressure cooker is an example of Gay Lussac's law as the temperature increases causing the pressure to increase above the food that's being cooked which make s it faster to be coo ked
9. 0 0.5 1 1.5 2 2.5 3 3.5 0 10 20 30 40 50 P bar Volume PV(n.m) Result :- Compression:- (boyle law) time P bar Volume PV(n.m) 0 0.93 3 2.79 12 1.12 2.5 2.8 21 1.33 2 2.66 34 1.65 1.5 2.45 46 0.23 1 0.23
10. Discussion :- Boyle's law: At constant temperature of the gas, the volume of a given mass of a gas is inversely proportional to its pressure. So, Boyle's law is talking about isothermal condition,right? But, what if temperature is not constant? My thinking: Suppose, there is a given gas in a frictionless cylinder fitted with a piston. Its initial temperature is t0t0 and its pressure is p0p0 . It is at equilibrium initially and hence the piston will also exert pressure p0p0 so as to maintain mechanical equilibrium. Now heat is applied to it by a burner. As the gas gains thermal energy, the gas' temperature increases from t0t0 to tktk . Now as the molecules have more KE, the pressure exerted by the gas on the piston will be more now. And the gas will expand now as a result of which volume increases. But now, the pressure of the gas is low now as the KE is used to displace the piston. And so finally, we can write P∝1vP∝1v which is what Boyle's law says but temperature being same.
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