What is the correct value of the gas constant R ?
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Answer: A. 0.0821 atm dm3k-1mol-
Explanation
The ideal gas constant R has a standard value of zero point zero eight two one atmosphere decimeters cubed per kelvin per mole. This specific numerical value is used when pressure is measured in atmospheres and volume in cubic decimeters. Unit conversion factors ensure that the gas law equation balances correctly under these specified conditions. The ideal gas law relates pressure, volume, temperature, and moles of gas through the constant R. Decimeters cubed are dimensionally equivalent to liters, making this unit common in laboratory chemistry. Gas constant values vary depending on the specific units chosen for pressure, volume, and energy.
Option B incorrectly specifies meters cubed instead of decimeters cubed for the volume dimension. Option C expresses the constant in calories, which represents an energy unit rather than standard pressure-volume units. Option D uses SI units of pressure and area, which corresponds to joules per kelvin per mole rather than liter-atmospheres.
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