Final answer:
The correct statement about Bohr's model of the atom is that electrons move in fixed orbits. These orbits correspond to specific energy levels, with higher energy orbits further from the nucleus. Electrons must absorb energy to move to higher orbits and emit energy when falling back to lower orbits, which can be seen in the distinct emission spectrum of hydrogen.
Step-by-step explanation:
In Bohr's model of the atom, the true statement is: a) Electrons move about in fixed orbits. According to Niels Bohr, electrons orbit the nucleus at specific, unchanging energy levels and do not emit energy while in these fixed orbits. Each orbit corresponds to a certain energy level, and these energy levels are analogous to the rungs of a ladder, with electrons able to jump between these fixed points.
Higher energy orbits are located further from the atomic nucleus because negative electrons are attracted to the positive protons in the nucleus. It thus takes energy to move the electrons away from the nucleus of the atom. When an electron moves to a higher energy orbit, it must absorb energy, and when it returns to a lower energy orbit, it releases energy in the form of light.
The emission spectrum of hydrogen can be accurately predicted by Bohr's model because the energy levels in hydrogen are predictable and distinct. When electrons jump to lower energy levels, they emit energy at specific wavelengths that correspond to the hydrogen spectral lines.