Two H atoms in the ground state collide in-elastically. The maximum amount by which their combined kinetic energy is reduced is
A. 10.20 eV
B. 20.40 eV
C. 13.6 eV
D. 27.2 eV
The answer is the option (a).
Total energy: Total energy (E) is the sum of both potential energy and kinetic energy, I.e. E = K + U
(a) 10.20 eV
The lowest state of the atom, called the ground state is that of the lowest energy the energy of this state (n=1), E1 is -13.6 eV
Let us take two hydrogen atoms in the ground state. When two atoms will collide inelastically, total energy associated with the H atoms –
=2 X (13.6 eV)=27.2 eV
The maximum amount of energy by which their combined kinetic energy is reduced when any one of them goes into a first excited state (n = 2) after the inelastic collision.
Thus, the total energy associated with the two H atoms after the collision is -
Hence the maximum loss of their combined kinetic energy
=27.2-17.0=10.2 eV
Therefore option (a) 10.20 eV is the right option.