Final answer:
The student asks to find the volume of argon at STP using the combined gas law, which involves initial conditions and a formula to solve for the required volume change when pressure and temperature are converted to standard units.
Step-by-step explanation:
The question involves using the combined gas law to calculate the volume of argon at standard temperature and pressure (STP), which is defined as 0°C (273K) and 1 atmosphere (atm) of pressure. Given the initial conditions for argon (250 cm³, -44°C, 712 mmHg), we must first convert the conditions to appropriate units (-44°C to 229K and 712mmHg to 0.9368 atm). We then apply the combined gas law formula (P1V1/T1 = P2V2/T2), with P1, V1, and T1 being the initial pressure, volume, and temperature, and P2, V2 and T2 being the conditions at STP.
The combined gas law rearranged to solve for V2 (the volume at STP) is V2 = (P1V1T2)/(P2T1). After substituting the corresponding values and solving, we can find the volume of the gas at STP. It's important to note that at STP, one mole of an ideal gas occupies 22.4 liters, which is the molar volume at these conditions.