What is Boyle's law: Definition and 41 Discussions

Boyle's law, also referred to as the Boyle–Mariotte law, or Mariotte's law (especially in France), is an experimental gas law that describes how the pressure of a gas tends to decrease as the volume of the container increases. 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 as:

or

where P is the pressure of the gas, V is the volume of the gas, and k is a constant.
The equation states that the product of pressure and volume is a constant for a given mass of confined gas and this holds 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:





P

1



V

1


=

P

2



V

2


.


{\displaystyle P_{1}V_{1}=P_{2}V_{2}.}
This 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.

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  1. patric44

    Percentage change in the density of a gas

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  2. blinkz303

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  3. L

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  4. WMDhamnekar

    MHB Exploring Robert Boyle's Law: Pressure and Volume of CO2

    Robert Boyle's law states that at constant temperature, the pressure of fixed amount ( i-e number of moles n) of gas varies inversely with its volume. Mathematically, it can be written as $p ∝ \frac1V $(at constant T and n) $\Rightarrow p = k_1 \times \frac1V $ where $k_1$is a proportionality...
  5. rjomega

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  6. H

    B Boyle's law vs the Venturi effect

    So this is something I been thinking about. In venturi principle when a fluid or gas is moving across a tube when it is constricted the fluid has increased velocity. Because it in constriction the pressure goes down. But in Boyle law if volume is decreased the pressure goes up. So in the...
  7. nmsurobert

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  8. patric44

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  10. D

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  11. K

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  12. R

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  13. Z

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  14. Y

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    Homework Statement The helium in the cylinder has a volume of 6.0 × 10^–3 m3^-1 (0.0060 m^3) and is at a pressure of 2.75 × 10^6 Pa. (i) The pressure of helium in each balloon is 1.1 × 10^5 Pa. The volume of helium in an inflated balloon is 3.0 × 10^–3 (0.0030 m3). The temperature of the...
  15. G

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  16. A

    What is the independent variable in Boyle's Law?

    I asked my teacher, and I was told that volume is the independent variable, and that pressure is dependent. The textbook I'm using said the same thing. After looking up some graphs of the law, I found that both pressure and volume were used as independent variables. It seems counter-intuitive...
  17. 2

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    In my textbook, it says that pV=C (Boyle's Law), V/T=C (Charle's Law) and that P/T=C (pressure Law). The problem is that I cannot see how the first two equations combine to give the last one. If I divide the first equation by the second, I get that pT=C, which certainly is not the same as the...
  18. Entanglement

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  19. L

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    I have been trying to find out of Boyle's Law and plate tectonics are in any way shape or form related. Are they? If they are not, is there a way I can relate their movement to physics?
  20. S

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    When we use Boyle's Law it means that as pressure increases the volume of the container would decrease. In my notes they stated that if I were to halve the volume there would be two times the number of collisions per second which implies that the force exerted is doubled. But why is this so? I...
  21. C

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  22. F

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  23. L

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  27. H

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  29. D

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  36. Amith2006

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  38. Z

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  39. N

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  41. F

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