– Water boils at 100 degrees Celsius at STP (Standard Temperature and Pressure).
– During boiling, liquid water is converted into gas state.
– Boiling occurs throughout the liquid.
You might be thinking why the hell am i saying this. You all knew it since childhood. But still, most of you are as if you didn’t know this at all. How?
While you are cooking something in water, it is not necessary that you see huge amounts of bubbles coming out of it. It won’t cook faster if you put a stronger flame beneath it. You are just wasting energy and money. Let me explain
dQ = dU + dW
The first law of Thermodynamic says that the heat supplied to a system equal to the change in its internal energy and the work done by the system.
But what happens at the boiling point?
All the energy being supplied to the system is used to do work (i.e. evaporate the water). We call this energy latent heat of vaporization. This is because the change in internal energy is zero. Simple algebra 😛
If you are evaporating less water, you can put less water at the beginning. The water will warm sooner and your meal will be ready sooner 😉
Boiling occurs throughout a liquid. Water at the bottom is not hotter than those at the surface 😉
Summary:
– Your food won’t cook faster if you put a bigger flame when its already boiling.
– You can lower the flame at the boiling point so as only to maintain the temperature.
– Time is money. Energy is money. Saving both allows you to have 2x economy,
– You just made one step to save the planet by being eco-friendly 😀
It won’t cook faster ? u bet ! it will be doomed ! haha.. what about superheated water ?? what about specific latent heat ?
As far as i know being myself a great cook(niahahaaha) if at boiling point you lower the gas by even a little, the water stops immediately to boil ! try it and see 😉
@ashfaq: Once the water reaches the boiling point, the temperature cannot not increase more unless all the water becomes steam. Superheated water hence does not exist.
If you see huge amount of bubbles coming out, then you know you can lower the gas a little.
@Nayar – whenever you bouillie a mine appollo cover the deksi with a cover it might be enough to increase the pressure and you would be having superheated water .. also try this link http://en.wikipedia.org/wiki/Superheated_water for more information
Nayar – HSC physics contains a lot of BS and they teach a lot of lies ( actually not lies but that’s the extent they think students are able to grasp in order not to be confused ! ) – If you do science at Univ or Engineering .. you will learn that what you have been taught at college is quite different.
I said under standard temperature and pressure. Under high pressure, water can indeed go at a much higher temperature 🙂
why don’t i receive email notifications when you reply ??
because i am on free hosting and my host disabled mailing feature 🙁
and i kept waiting for an answer !! lolzz..
Thank you for any other great post. Where else may anybody get that kind of information in such a perfect way of writing? I’ve a presentation next week, and I am at the search for such info.