Question 1

What happens to electrons when an atom absorbs energy?

Accepted Answer

When an atom absorbs energy, electrons become excited and move from the ground state to higher energy levels. According to the Bohr Model, electrons occupy discrete energy states labeled by the quantum number n. An electron can only transition between these specific orbits if the absorbed energy exactly equals the difference between two energy states.

Question 2

Why do different elements produce different spectral lines?

Accepted Answer

Each element has unique energy level spacing, so electrons transitioning between states release different amounts of energy. Since the wavelength of emitted light depends on the energy difference between levels, different atoms produce distinct spectral lines. This variation allows scientists to identify elements by their characteristic emission spectra.

Question 3

What defines the Balmer Series in hydrogen?

Accepted Answer

The Balmer Series consists of visible spectral lines produced when hydrogen electrons transition from higher energy levels down to n=2. Johann Balmer observed four main lines at 410, 434, 486, and 656 nm, corresponding to transitions from n=6, 5, 4, and 3 respectively. The red h-alpha line at 656 nm results from the n=3 to n=2 transition.

Question 4

How does the Rydberg equation predict spectral line wavelengths?

Accepted Answer

The Rydberg equation combines the Bohr Model with empirical observations to calculate wavelengths of emitted light. It uses the Rydberg constant, the initial energy level (n-initial), and final energy level (n-final) to determine the wavelength. For the Balmer Series, n-final equals 2, allowing prediction of all visible hydrogen spectral lines.

Question 5

What is the relationship between energy difference and emitted light wavelength?

Accepted Answer

The wavelength of emitted light is directly determined by the energy difference between two energy levels. Larger energy differences produce higher-energy light with shorter wavelengths, while smaller differences produce lower-energy light with longer wavelengths. This relationship allows scientists to calculate energy transitions from observed spectral line positions.

Question 6

Why does the emission spectrum appear as discrete lines rather than a continuous spectrum?

Accepted Answer

Pure elemental samples produce discrete spectral lines because electrons can only occupy specific energy levels and transition between them. Each transition releases a precise amount of energy corresponding to a single wavelength. In contrast, mixed molecular samples produce continuous spectra because they contain many different possible transitions.

Question 7

How did Johann Balmer quantify the visible hydrogen spectral lines?

Accepted Answer

Balmer developed an empirical formula relating observed wavelengths to quantum numbers, using a constant value and the lower energy level of 2. His formula successfully predicted the four visible hydrogen lines and was later refined by Johannes Rydberg into a more general equation. This mathematical relationship bridged observation and the Bohr Model's theoretical framework.

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