Define lonisation energy. What is the lonization energy of hydrogen atom ?

Define Activation Energy.

What is the value of first excitation energy of hydrogen atom ?

What is energy? What is its unit?

What is energy ?

Define- Internal energy.

Define ionization energy. Name the factors on which ionisation energy depends? How does it vary down the group and across a period?

What is rolling kinetic energy ?

What is potential energy ?

Define excitation energy, binding energy and ionization energy of an electron in an atom.

Define the following: Energy