Question

What does Bohr's model depict?

• A. The spectrum of hydrogen atom only
• B. The spectrum of atom or ion containing one electron only
• C. The spectrum of hydrogen molecule
• D. The solar spectrum

Answer 1

The correct option is B

The spectrum of atom or ion containing one electron only

The explanation for correct option:

(B) The spectrum of an atom or ion containing one electron only

Bohr's Model:

• According to the Bohr model, the atom has a central nucleus made up of protons and neutrons, with the electrons orbiting the nucleus at precise intervals.
• In an atom, negatively charged electrons move in fixed circular paths around the positively charged nucleus that are referred to as orbits or shells.
• A lower energy level to a higher energy level is reached by an atom's electrons by obtaining the necessary energy, and a higher energy level to a lower energy level by losing energy.
• These orbits create electron shells or energy levels, which allow us to see how many electrons are present in each shell.
• The number and the letter "n" are used to identify these energy levels.

Figure: Electrons orbiting the nucleus in shells at a fixed distance

• Bohr's hypothesis is applicable to entities that are similar to hydrogen but only have one electron, such ${\mathrm{Li}}^{2+}$. Atoms similar to hydrogen are amenable to Bohr's hypothesis (single electron system). Only one electron makes up ${\mathrm{Li}}^{2+}$ and the ${\mathrm{H}}^{{+}^{}}$ atom.

The explanation for the incorrect option:

(A) The spectrum of hydrogen atoms only

• Though Bohr's theory is applicable to the Hydrogen atom but it is also applicable to Lithium too.
• It is applicable for species with one electron only and Lithium satisfies the condition.

(C) The spectrum of the hydrogen molecule

• The hydrogen molecule comprises two Hydrogen atoms.
• The theory is applicable to both hydrogen and lithium atoms.

(D) The solar spectrum

• Thousands of dark absorption lines are superposed in a continuum that makes up the solar spectrum.
• It is a fully electromagnetic spectrum.

Hence option (B) is correct.