Why is it important to convert temperature to units of kelvin before using the ideal gas law?

• A. Because the ideal gas law requires absolute temperature to ensure proportionality between pressure, volume, and temperature.
• B. Because kelvin is the only temperature unit that can be measured experimentally.
• C. Because the gas constant R is only defined for temperatures in degrees Celsius.
• D. Because using Celsius or Fahrenheit would result in negative values for pressure.

Answer: (A)

Verified step by step guidance

1. Understand that the ideal gas law is given by the equation \(P V = n R T\), where \(P\) is pressure, \(V\) is volume, \(n\) is the number of moles, \(R\) is the gas constant, and \(T\) is the temperature.
2. Recognize that the temperature \(T\) in the ideal gas law must be in an absolute scale, meaning it starts at absolute zero, where molecular motion theoretically stops.
3. Know that the Kelvin scale is an absolute temperature scale starting at absolute zero (0 K), unlike Celsius or Fahrenheit which can have negative values.
4. Realize that using Celsius or Fahrenheit directly in the ideal gas law would break the proportionality because these scales do not start at absolute zero, leading to incorrect or non-physical results.
5. Therefore, converting temperature to kelvin ensures that the relationship between pressure, volume, and temperature remains directly proportional and physically meaningful in the ideal gas law.