Question

In a pressure cooker, a lid is screwed tightly onto a pot so that the air pressure in the pot is increased. What effect, if any, will this have on the boiling point of water in the pot?
The boiling point will be raised.
The boiling point will be lowered.
The boiling point will be unaffected.
None of the above.

Answer 1

If a lid is screwed on tightly in a pressure cooker, the air pressure is increased. This will make the boiling point of the water to be raised. 

Answer 2

A liquid boils when it's vapor pressure will be equal to the atmospheric pressure. With the lid on, increases the pressure inside the pot. As an effect, it would take a higher temperature to reach the boiling temperature. 

Answer: The boiling point will be raised. <span />