Choose the most correct option.
Pressure cooker reduces cooking time for food because _______.
Options
boiling point of water involved in cooking is increased
heat is more evenly distributed in the cooking space
the higher pressure inside the cooker crushes the food material
cooking involves chemical changes helped by a rise temperature
Solution
Pressure cooker reduces cooking time for food because boiling point of water involved in cooking is increased.
Explanation:
The boiling point of a substance is the temperature at which the vapour pressure of a liquid equals the pressure surrounding the liquid and the liquid changes to vapour.
Normally, when we cook food, the temperature inside rises until the water begins to boil. The temperature of the system will not rise at boiling point because heat is utilised to boil the water.
However, when we cook food in a pressure cooker, the temperature at which water boils rises as the pressure within the pressure cooker rises.
As the surrounding pressure rises, so does the boiling point temperature. As a result, instead of boiling the water, the heat will raise the temperature of the system. Food cooks faster at higher temperatures because cooking reactions speed up.