Question

Which of the following electron transitions in hydrogen atom will require largest amount of energy?

• A. From $n=1$ to $n=2$
• B. From $n=2$ to $n=3$
• C. From $n=\infty$ to $n=1$
• D. From $n=3$ to $n=5$

Answer 1

The correct option is A From $n=1$ to $n=2$

The electron transition from $n=1$ to $n=2$ in hydrogen atom will require largest amount of energy.
The amount of energy is directly proportional to
$[\frac{1}{n_1^2}-\frac{1}{n_2^2}]$
This difference is maximum for the electron transition from $n=1$ to $n=2$
$[\frac{1}{1^2}-\frac{1}{2^2}]=0.75$