What is the charge in mass when 2 mole of hydroghen atoms combine to form 1 mole fo `H_(2)` molecule if: `2H rarr H_(2), Delta E = -436 kJ`? Comment on the result.

Explanation

Let total energy is obtained as a result of mass decay.
`Delta m = (Delta E)/(c^(2)) = (436xx10^(3))/((3.0xx10^(8))^(2))`
`= 4.84xx10^(-12)kg = 4.84xx10^(-9)g`
Thus loss is mass accompanying formation of 1 mole of `H_(2)` form its constrituent atoms is `4.84xx10^(9)g`. It is too small to be deterctable by any balance currently available. Thus the energy difference can be given due to attactions among `H-` atom to form `H-H` bond.