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A mixture of helium and oxygen is used in scuba diving tanks to help prevent ""the bends"". 46 L helium and 12 L oxygen are combined at 25°C and 1.0 atm in a tank with a total volume of 5.0 L. Determine the partial pressures of He and oxygen and the total pressure in the tank.

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Answer

given,

For helium

Volume,V = 46 L

Pressure,P = 1 atm

Temperature,T = 25°C  =  273 +25 = 298 K

R=0.0821 L . atm /mole.K

n₁ = ?

number of moles

we know

P V = n R T

[tex]n_1 =\dfrac{46 \times 1}{0.0821\times 298}[/tex]

  n₁ = 1.89 moles

For oxygen

Volume,V = 12 L

Pressure,P = 1 atm

Temperature,T = 25°C  =  273 +25 = 298 K

R=0.0821 L . atm /mole.K

n₂ = ?

number of moles

we know

P V = n R T

[tex]n_2 =\dfrac{12 \times 1}{0.0821\times 298}[/tex]

  n₂ = 0.49 moles

Total volume of tank = 5 L

temperature of tank = 298 K

Partial pressure of helium

[tex]P_1=\dfrac{n_1 R T}{V}[/tex]

[tex]P_1=\dfrac{1.89\times 0.0821\times 298}{5}[/tex]

     P₁ = 9.25 atm

Partial pressure of oxygen

[tex]P_2=\dfrac{n_2 R T}{V}[/tex]

[tex]P_2=\dfrac{0.49\times 0.0821\times 298}{5}[/tex]

    P₂ = 2.39 atm

total pressure

    P = P₁ + P₂

    P = 9.25 + 2.39

    P = 11.64 atm

The total partial pressure of the mixture is 11.58 atm.

How do you calculate the pressure?

Given that A mixture of helium and oxygen is used in scuba diving tanks to help prevent "the bends".

For helium, volume V is 46 L, pressure P is 1 atm, temperature T is 25 degrees C, the ideal gas constant R is 0.0821 L . atm /mole.K.

For oxygen, volume V is 12 L, pressure P is 1 atm, temperature T is 25 degrees C, the ideal gas constant R is 0.0821 L . atm /mole.K.

Temperature can be written as below.

T = 25°C  =  273 +25 = 298 K

The number of moles in helium can be calculated by the ideal gas law.

[tex]P V = n_h R T[/tex]

[tex]1\times 46 = n_h \times 0.0821 \times 298[/tex]

[tex]n_h = 1.88[/tex]

The number of moles in oxygen can be calculated by the ideal gas law.

[tex]PV = n_oRT[/tex]

[tex]1\times 12 = n_o\times 0.0821\times 298[/tex]

[tex]n_o = 0.49[/tex]

The total volume of the tank is 5 L and the temperature is 298 k.

So, the partial pressure of helium is given below.

[tex]P_hV = nRT[/tex]

[tex]P_h =\dfrac { 1.88\times 0.0821\times 298 }{5}[/tex]

[tex]P_h = 9.19 \;\rm atm[/tex]

The partial pressure of oxygen is given below.

[tex]P_oV = nRT[/tex]

[tex]P_o =\dfrac { 0.49\times 0.0821\times 298 }{5}[/tex]

[tex]P_o = 2.39 \;\rm atm[/tex]

The total partial pressure is given below.

[tex]P = P_h+P_o[/tex]

[tex]P = 9.19 +2.39[/tex]

[tex]P = 11.58\;\rm atm[/tex]

Hence the total partial pressure of the mixture is 11.58 atm.

To know more about partial pressure, follow the link given below.

https://brainly.com/question/14623719.