What temperature will hot tea become if it is left for 1 hour?

Answer 1

This is impossible to answer because this depends on where you live and where you leave the cup of tea, what temperature the tea is at the beginning.

Answer 2

This question may arise as water often cools to point below the temperature of the room it is sitting in. In this case the amount of water in a cup of tea is sufficiently small that the heat content will reduce to its stable point over the course of an hour.The exact temperature depends on:

• the temperature of the room it is in
  
• the surface area exposed to the air in the room
  
• the rate of heat transfer between the room air or table surface into the tea in the cup
  
• if there is significant air movement
  
• the relative humidity of the air around the cup
  

These conditions must be specified before an exact answer can be specified for any particular situation.

In general the tea temperature will be several degrees below the room temperature.

NOTE: If the tea cup is enclosed with a piece of saran wrap the temperature will fall to room temperature then stop as no evaporative cooling will occur.

If you want to predict, experimentally, what the temperature of the tea will be sonly construct the wet-bulb side of a Hygrometer. This is done by wrapping the end of a liquid filled thermometer in cotton batting, wetting the cotton batting with the liquid (or water) and either sucking air over the wet cotton with a vacuum cleaner or blowing air over it with a fan (NOTE: Don't blow over the bulb with your breath as the air from your lungs is warm and damp). The temperature pot the temperature indicated will fall until it stabilizes, usually at several degrees below room temperature. This is the temperature he cup of tea will usually arrive at within the hour.