Question 1

Which of the following statements best describes the main difference between the Bohr model and the quantum-mechanical model of the atom?

Accepted Answer

The Bohr model describes electrons as existing in fixed orbits with specific energies, while the quantum-mechanical model describes electrons as existing in orbitals that represent probability distributions.

Question 2

Which property of light is directly proportional to its energy?

Accepted Answer

Frequency

Question 3

A photon of which type of electromagnetic radiation has the highest energy?

Accepted Answer

Gamma rays

Question 4

What is the relationship between the wavelength ($$\lambda) $$and frequency ($$
u) of $$light?

Accepted Answer

They are inversely proportional: $$\lambda \propto \frac{1}{
u}$$

Question 5

Which of the following best explains why a red shirt appears red under white light?

Accepted Answer

The shirt reflects red light and absorbs all other colors.

Question 6

Which of the following electron configurations represents a ground-state carbon atom?

Accepted Answer

$$1s^2$$ $$2s^2$$ $$2p^2$$

Question 7

According to the quantum-mechanical model, what does an orbital represent?

Accepted Answer

A region of space where there is a high probability of finding an electron

Question 8

Which principle states that no more than two electrons can occupy the same orbital, and they must have opposite spins?

Accepted Answer

Pauli exclusion principle

Question 9

Which of the following elements has the greatest metallic character?

Accepted Answer

Sodium (Na)

Question 10

What is the maximum number of electrons that can occupy the 3d subshell?

Accepted Answer

10

Question 11

Which of the following correctly describes the trend in atomic size as you move down a group in the periodic table?

Accepted Answer

Atomic size increases

Question 12

Which element has the highest first ionization energy among the following?

Accepted Answer

Neon (Ne)

Question 13

A hydrogen atom emits a photon with a wavelength of 486 nm. According to the Bohr model, this emission corresponds to an electron transition from:

Accepted Answer

$$n=4$$ \rightarrow n=2$

Question 14

Which of the following is the correct noble gas core notation for the electron configuration of sulfur (S, atomic number 16)?

Accepted Answer

$$[Ne] 3s^2$ 3p^4$

Question 15

Which of the following best explains why noble gases are generally unreactive?

Accepted Answer

They have a full outer shell of s and p orbitals, totaling 8 valence electrons.

Question 16

Which of the following is the correct order of filling for the following orbitals in a multi-electron atom?

Accepted Answer

4s, 3d, 4p

Question 17

Which of the following statements about the periodic table is correct?

Accepted Answer

Elements in the same group have the same number of valence electrons.

Question 18

Which of the following is a real-world application of the emission spectra of elements?

Accepted Answer

Identifying elements in distant stars using their spectral lines

Question 19

Which of the following best describes Hund's rule?

Accepted Answer

Electrons fill orbitals of the same energy singly before pairing.

Question 20

Which of the following elements is expected to have the largest atomic radius?

Accepted Answer

Potassium (K)

Chapter 9: Electrons in Atoms and the Periodic Table – Study Notes

Study Guide - Practice Questions

Study Guide - Flashcards