Final answer:
In the visible spectrum of the hydrogen atom, four distinct lines appear as a result of electron transitions from higher to lower energy levels: a red line at 656 nm, a green line at 486 nm, a blue line at 434 nm, and a violet line at 410 nm. These lines correspond to transitions in the Balmer series and are observable when hydrogen gas is excited by an electric current.
Step-by-step explanation:
When you observe the hydrogen spectrum using the given simulation, you will see multiple lines appear in the visible portion of the spectrum. These lines occur due to electrons in the hydrogen atom moving to higher energy levels and then emitting photons as they return to lower energy levels. When a hydrogen gas is placed in a tube with an electric current passed through it, it emits light that, when split by a prism, shows four individual frequencies or colors within the visible spectrum. These appear as red, blue-green, blue, and violet lines. Specifically, the transitions correspond to the Balmer series: the n = 3 to n = 2 transition giving rise to the black line at 656 nm (red), the n = 4 to n = 2 transition to the line at 486 nm (green), the n = 5 to n = 2 transition to the line at 434 nm (blue), and the n = 6 to n = 2 transition to the line at 410 nm (violet). These observations tie in with the concept that each element has a unique emission spectrum, which is used for element identification.