According to Avogadro's law, which is part of gas laws in chemistry, the number of moles of gas (n) and its volume (V) at a given temperature and pressure are directly proportional. In the scenario provided, the initial volume is 500 mL with 2.50 moles of the gas. When the volume is increased to 750 mL at constant temperature and pressure, the number of moles of the gas would remain the same because there is no mention of gas being added to or removed from the system. Therefore, the sample originally occupying 500mL still contains 2.50 moles when it occupies 750mL.
The number of moles in the gas sample remains the same when the volume changes from 500 mL to 750 mL, according to Avogadro's Law. Since temperature and pressure are constant, the gas still contains 2.50 moles. Changes in volume do not affect the moles as long as no gas is added or removed.
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