STP (Standard Temperature and Pressure) is defined as a temperature of 0 degrees Celsius (273.15 Kelvin) and a pressure of 1 atmosphere (atm) or 760 mmHg. To determine the volume of the gas at STP, we can use the combined gas law, which states:
(P1 * V1) / (T1) = (P2 * V2) / (T2)
Where: P1 = initial pressure (in mmHg) V1 = initial volume (in liters) T1 = initial temperature (in Kelvin) P2 = final pressure (in mmHg, which is the STP pressure of 760 mmHg) V2 = final volume (unknown) T2 = final temperature (in Kelvin, which is 0 degrees Celsius or 273.15 Kelvin)
Rearranging the equation, we have:
V2 = (P1 * V1 * T2) / (P2 * T1)
Let's substitute the given values into the equation:
P1 = 1800 mmHg V1 = 2 liters T1 = 135 °C + 273.15 = 408.15 Kelvin P2 = 760 mmHg T2 = 0 °C + 273.15 = 273.15 Kelvin
Now we can calculate V2:
V2 = (1800 * 2 * 273.15) / (760 * 408.15) V2 ≈ 1.228 liters
Therefore, the volume of the gas at STP would be approximately 1.228 liters.