[brunetteangel]

The problem is this:

Calculate how much heat is being released in the reaction of white phosphorus turning into red phosphorus if the mass of white phosphorus is 1000 kg. Standard enthalphy of this reaction is -16,73 kJ/mol.

Now, I tried solving it using proportion, like this:

                   P4 -> Pn

            123,89g ... -16,73kJ
        1.000.000g  ...      x

But when I calculate x, I get 135.033,6543 kJ, and the solution at the back of the book is different, it's 5,4 * 10^5 kJ. Can someone please tell me where did I make mistakes? Thanks.