Final answer:
According to Boyle's Law, the volume of the gas can be calculated using the initial and final pressures. The volume is found to be 1000 ml.
Step-by-step explanation:
To solve this problem, we can use Boyle's Law, which states that the product of pressure and volume is constant at constant temperature. Since the temperature remains the same, we can set up the equation:
P1V1 = P2V2
Plugging in the given values:
1 atm * 500 ml = 0.5 atm * V2
Solving for V2:
V2 = (1 atm * 500 ml) / 0.5 atm = 1000 ml
Therefore, the gas now occupies a volume of 1000 ml at the high altitude with a pressure of 0.5 atm.