Question

As an electron makes a transition from an excited state to the ground state of a hydrogen- like atom/ion

• A. kinetic energy, potential energy and total energy decrease
• B. kinetic energy decreases, potential energy increases but total energy remains same
• C. kinetic energy and total energy decrease but potential energy increases
• D. its kinetic energy increases but potential energy and total energy decrease

Answer 1

Answer: (D)

its kinetic energy increases but potential energy and total energy decrease

Answer 2

$E _{\text {Total }}=-13.6 \,eV \frac{ Z ^{2}}{ n ^{2}}$
$KE =\left| E _{\text {Total }}\right|$
$PE =2 \,E _{\text {total }}$
As n decreases, Total energy decreases, potential energy decreases and kinetic energy increases.