Spaghetti takes about 9 minutes to cook at sea level, but about 14 minutes in the mountains. why do you think this happens?

Water boils when the vapor pressure of the water equals the atmospheric pressure that's pressing down on it. Water boils at a lower temperature (more easily) at higher elevations (like on mountains), because:

- Atmospheric pressure is lower at higher elevation

- Easier for vapor pressure to equal this lower atmospheric pressure

Since the water boils at a lower temperature, it takes longer for the pasta to cook.