Why does it always take 4 min to boil an egg properly

Most people prefer their eggs to be lightly boiled, with the yellow yolk still liquid and the albumen solid and white. We say the egg white has been denatured . The variation in egg size is not great. An average egg contains essentially a constant amount of yolk and albumen, so the energy necessary to heat both the yolk and albumen (and to denature the albumen) is, more or less, the same for any egg. 

This simple example introduces the topic of thermochemistry. 

The overall heat capacity of the calorimeter is a simple function of the amount of steel the bomb comprises and the amount of water surrounding it. If the mass is m and the heat capacity is C, then the overall heat capacity is expressed by 

Thermochemistry is the branch of thermodynamics concerned with the way energy is transferred, released or consumed during a chemical reaction. 

If the amount of compound burnt in the calorimeter is n, and remembering that no work is done, then a combination of Equations (3.7) and (3.8) suggests that the change in internal energy occurring during combustion is given by 

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