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At 27°C and 750 mmHg, a gas occupies 380 cm^3. What is the volume of this gas at STP?

User Griff
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The volume of the gas at STP is approximately 341.3 cm^3.

To find the volume of the gas at STP, we can use the ideal gas law:

PV = nRT

where:

P is the pressure

V is the volume

n is the number of moles

R is the ideal gas constant (approximately 8.314 J/mol*K)

T is the temperature in Kelvin

We can rearrange the equation to solve for the volume at STP:

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

where:

V1 is the initial volume (380 cm^3)

T1 is the initial temperature (27°C + 273.15 K = 300.15 K)

P1 is the initial pressure (750 mmHg)

V2 is the final volume (unknown)

T2 is the STP temperature (0°C + 273.15 K = 273.15 K)

P2 is the STP pressure (760 mmHg)

Converting the units:

V1 = 380 cm^3 * (1 L / 1000 cm^3) = 0.38 L

P1 = 750 mmHg * (1 atm / 760 mmHg) = 0.987 atm

Plugging the values into the equation:

V2 = 0.38 L * 273.15 K * 0.987 atm / (300.15 K * 0.987 atm)

V2 ≈ 0.341 L ≈ 341.3 cm^3

User Onnonymous
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