Final answer:
1 mole of a gas at STP has a standard volume of 22.4 L, applicable to all ideal gases under those conditions.
Step-by-step explanation:
The question '1 mole of a gas at STP has a volume of?' is asking about the volume that one mole of any gas occupies at standard temperature and pressure (STP), which is defined as 0°C (or 273 K) and 1 atm of pressure. According to the ideal gas law and the concept of molar volume, at STP, any gas will have a volume of 22.4 L per mole. This information serves as a useful conversion factor in stoichiometry problems when the conditions are at STP. The molar volume at STP remains constant and is independent of the type of gas, so no matter what the gas is, 1 mole will occupy 22.4 L of volume.