By using Einstein's formulated equation E=MC^2 !

WHAT IS THE INCREASE IN MASS WHEN 4200 JOULES OF HEAT IS ABSORBED BY 1KG OF WATER TO CAUSE A TEMPERATURE RISE OF 1K?
(Take the velocity of light c=3*10^8 ms^-1.)

Solution :-

M=E/c^2
M=4200/(3*10^8)^2

M=4.7*10^-14
that is the increase in mass!?

NOW, my question is, whay there is an increase in mass? i understand that energy is directly proportional to mass but considering EXOTHERMIC reaction "ENERGY IS REALESED WHEN BONDS ARE MADE"
but in the situation ENERGY is taken IN but still bond is made!.why ?

• Oh my aching chemistry back! - rick_crockett - April 19, 2007 - 08:39 UTC