Q: A dental hygienist uses x-rays with a wavelength of $$1.00\ \text{Å} to $$take radiographs. What is the frequency of this radiation? (Speed of light $$c = 3.00 \times 10^8$\ \text{m/s})$$

$$3.00 \times 10$$^{18}$$\ \text{s}^{-1}$$

Q: A cook uses a microwave oven with radiation of wavelength $$1.20\ \text{cm}. $$What is the energy of one photon of this radiation? ($$h = 6.626 \times 10$$^{-34}$$\ \text{J} \cdot \text{s}$$, $$c = 3.00 \times 10^8$\ \text{m/s})$$

$$1.66 \times 10$$^{-23}$$\ \text{J}$$

Question 1

Which of the following statements best explains why the Bohr model only works for the hydrogen atom and not for multi-electron atoms?

Accepted Answer

The Bohr model does not account for electron-electron repulsions present in multi-electron atoms.

Question 2

A dental hygienist uses x-rays with a wavelength of $$1.00\ 	ext{Å} to $$take radiographs. What is the frequency of this radiation? (Speed of light $$c = 3.00 	imes 10^8$\ 	ext{m/s})$$

Accepted Answer

$$3.00 	imes 10$$^{18}$$\ 	ext{s}^{-1}$$

Question 3

Which quantum number determines the shape of an atomic orbital?

Accepted Answer

Angular momentum quantum number ($$l)$$

Question 4

A cook uses a microwave oven with radiation of wavelength $$1.20\ 	ext{cm}. $$What is the energy of one photon of this radiation? ($$h = 6.626 	imes 10$$^{-34}$$\ 	ext{J} \cdot 	ext{s}$$, $$c = 3.00 	imes 10^8$\ 	ext{m/s})$$

Accepted Answer

$$1.66 	imes 10$$^{-23}$$\ 	ext{J}$$

Question 5

Which of the following best describes Hund’s Rule?

Accepted Answer

Electrons occupy degenerate orbitals singly with parallel spins before pairing.

Question 6

Calculate the wavelength (in nm) of a photon released when an electron jumps from level $$n=5 to$$ $$n=2 in a $$hydrogen atom. ($$R_H = 2.18 	imes 10$$^{-18}$$\ 	ext{J}$$, $$c = 3.00 	imes 10^8$\ 	ext{m/s}$$, $$h = 6.626 	imes 10$$^{-34}$$\ 	ext{J} \cdot 	ext{s})$$

Accepted Answer

$$434\ 	ext{nm}$$

Question 7

Which of the following is a correct set of quantum numbers for the third electron in a fluorine atom?

Accepted Answer

$$n=2,\ l=0,\ m_l=0,\ m_s=+\frac{1}{2}$$

Question 8

Which of the following statements about the Pauli Exclusion Principle is correct?

Accepted Answer

No two electrons in the same atom can have the same set of four quantum numbers.

Question 9

Which equation correctly relates the wavelength ($$\lambda) $$and frequency ($$
u) of $$electromagnetic radiation?

Accepted Answer

$$c = \lambda 
u$$

Question 10

Which of the following electron configurations represents a transition metal?

Accepted Answer

$$[Ar] 4s^2$ 3d^5$

Question 11

A hydrogen atom absorbs a photon and its electron moves from $$n=1 to$$ $$n=4. $$What is the sign of $$\Delta E$$ and what does it mean?

Accepted Answer

$$\Delta E is $$positive; energy is absorbed.

Question 12

Which quantum number describes the orientation of an orbital in space?

Accepted Answer

Magnetic quantum number ($$m_l)$$

Question 13

Which of the following best describes the difference between s, p, and d orbitals?

Accepted Answer

s orbitals are spherical, p orbitals are dumbbell-shaped, d orbitals have four lobes.

Question 14

According to de Broglie, what is the wavelength of an electron (mass $$9.11 	imes 10$$^{-31}$$\ 	ext{kg}) $$moving at $$1.00 	imes 10^6$\ 	ext{m/s}$$? ($$h = 6.626 	imes 10$$^{-34}$$\ 	ext{J} \cdot 	ext{s})$$

Accepted Answer

$$7.27 	imes 10$$^{-10}$$\ 	ext{m}$$

Question 15

Which of the following is a consequence of the Heisenberg Uncertainty Principle?

Accepted Answer

It is impossible to know both the exact position and momentum of an electron simultaneously.

Question 16

Which of the following electron configurations is correct for sodium (Na, atomic number 11)?

Accepted Answer

$$1s^2$$ $$2s^2$$ $$2p^6$$ $$3s^1$$

Question 17

Which of the following best describes the relationship between wavelength and frequency for electromagnetic radiation?

Accepted Answer

As wavelength increases, frequency decreases.

Question 18

Which of the following is a condensed electron configuration for selenium (Se, atomic number 34)?

Accepted Answer

$$[Ar] 4s^2$ 3d$$^{10}$$ 4p^4$

Question 19

Which of the following is true about the energy of orbitals in a many-electron atom?

Accepted Answer

Orbitals in the same sublevel are degenerate, but sublevels can have different energies.

Chapter 6: Electronic Structure of Atoms – Study Notes

Study Guide - Practice Questions

Study Guide - Flashcards