Why does a sealed bag of chips expand when you take it to a higher altitude?

• A. The external air pressure decreases at higher altitude, so the pressure inside the bag becomes greater than the outside, causing the bag to expand.
• B. The volume of the bag decreases at higher altitude due to lower pressure.
• C. The number of gas molecules inside the bag increases at higher altitude, causing expansion.
• D. The temperature at higher altitude is higher, causing the gas inside the bag to expand.

Answer: (A)

Verified step by step guidance

1. Understand that the bag of chips contains gas trapped at a certain pressure and volume at the original altitude.
2. Recall that atmospheric pressure decreases as altitude increases, meaning the external pressure on the bag becomes lower at higher altitudes.
3. Apply the concept of pressure difference: when the pressure inside the bag is greater than the external pressure, the bag will expand to balance the forces.
4. Use the ideal gas law relationship, where pressure and volume are inversely related at constant temperature and number of moles: \(P \times V = \text{constant}\) (Boyle's Law).
5. Conclude that since external pressure decreases and the gas inside the bag remains roughly constant in amount and temperature, the volume of the bag increases, causing it to expand.