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18 votes
18 votes
3. At 35 C, a sample of gas has a volume of 256 ml and a pressure of 720.torr. What would the volume

be if the temperature were changed to 22 C and the pressure to 1.25 atmospheres

User Hsm
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1 Answer

23 votes
23 votes

Answer:

The volume will be 185.83 mL.

Step-by-step explanation:

Gay-Lussac's law indicates that when there is a constant volume, as the temperature increases, the pressure of the gas increases. And when the temperature is decreased, the pressure of the gas decreases. Gay-Lussac's law can be expressed mathematically as follows:


(P)/(T) =k

Where P = pressure, T = temperature, k = Constant

Boyle's law says that the volume occupied by a given gaseous mass at constant temperature is inversely proportional to pressure. Boyle's law is expressed mathematically as:

P*V=k

Where P = pressure, V = volume, k = Constant

Finally, Charles's Law consists of the relationship that exists between the volume and the temperature of a certain quantity of ideal gas, which is kept at a constant pressure. For a given sum of gas at a constant pressure, as the temperature increases, the volume of the gas increases and as the temperature decreases, the volume of the gas decreases because the temperature is directly related to the energy of the movement of the gas molecules. .

In summary, Charles's law is a law that says that when the amount of gas and pressure are kept constant, the quotient that exists between the volume and the temperature will always have the same value:


(V)/(T) =k

Combined law equation is the combination of three gas laws called Boyle's, Charlie's and Gay-Lusac's law:


(P*V)/(T) =k

Studying two different states, an initial state 1 and a final state 2, it is satisfied:


(P1*V1)/(T1) =(P2*V2)/(T2)

In this case:

  • P1= 720 torr
  • V1= 256 mL
  • T1= 35 C= 308 K (being 0 C= 273 K)
  • P2= 1.25 atm= 950 torr (being 1 atm= 760 torr)
  • V2= ?
  • T2= 22 C= 295 K

Replacing:


(720 torr*256 mL)/(308 K) =(950 torr*V2)/(295 K)

Solving:


V2= (295K)/(950 torr) *(720 torr*256 mL)/(308 K)

V2= 185.83 mL

The volume will be 185.83 mL.

User Luis Cardoza Bird
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