Q: A photon in the visible region has a frequency of $$5.0 \times 10$$^{14}$$\ \mathrm{Hz}. $$What is its energy?

$$E = 3.3 \times 10$$^{-19}$$\ \mathrm{J}$$

Q: If a hydrogen atom absorbs a photon and its electron transitions from $$n=2 to$$ $$n=5$$, what is the energy of the absorbed photon?

$$E = 4.58 \times 10$$^{-19}$$\ \mathrm{J}$$

Q: A laser pulse has a wavelength of $$450\ \mathrm{nm}$$ and a total energy of $$0.800\ \mathrm{mJ}. $$How many photons are emitted in the pulse? ($$h = 6.626 \times 10$$^{-34}$$\ \mathrm{J\cdot s}$$, $$c = 3.00 \times 10^8$\ \mathrm{m/s})$$

$$1.8 \times 10$$^{15}$$ photons

Q: A material has a binding energy of $$2.0 \times 10$$^{-19}$$\ \mathrm{J}. If it is $$struck by photons of energy $$3.0 \times 10$$^{-19}$$\ \mathrm{J}$$, what is the kinetic energy of the ejected electrons?

$$1.0 \times 10$$^{-19}$$\ \mathrm{J}$$

Question 1

Which of the following best explains why the emission spectrum of hydrogen consists of distinct lines rather than a continuous spectrum?

Accepted Answer

Electrons in hydrogen atoms transition between quantized energy levels, emitting photons of specific energies.

Question 2

Given the energy levels for hydrogen: $$E_1 = -2.18$$ 	imes $$10^{-18}$$\ \mathrm{J}$$, E_2$ = -5.45 	imes 10$$^{-19}$$\ \mathrm{J}$$, $$E_3 = -2.42$$ 	imes $$10^{-19}$$\ \mathrm{J}$$, which transition corresponds to the absorption of the greatest energy?

Accepted Answer

From $$n=1 to$$ $$n=\infty$$

Question 3

A photon in the visible region has a frequency of $$5.0 	imes 10$$^{14}$$\ \mathrm{Hz}. $$What is its energy?

Accepted Answer

$$E = 3.3 	imes 10$$^{-19}$$\ \mathrm{J}$$

Question 4

Which statement correctly describes the difference between the absorption and emission spectra of helium?

Accepted Answer

The absorption spectrum shows dark lines where photons are absorbed, while the emission spectrum shows colored lines where photons are emitted.

Question 5

If a hydrogen atom absorbs a photon and its electron transitions from $$n=2 to$$ $$n=5$$, what is the energy of the absorbed photon?

Accepted Answer

$$E = 4.58 	imes 10$$^{-19}$$\ \mathrm{J}$$

Question 6

Which of the following best describes the relationship between wavelength ($$\lambda$$), frequency ($$
u$$), and speed of light ($$c$$)?

Accepted Answer

$$c = \lambda 
u$$

Question 7

A laser pulse has a wavelength of $$450\ \mathrm{nm}$$ and a total energy of $$0.800\ \mathrm{mJ}. $$How many photons are emitted in the pulse? ($$h = 6.626 	imes 10$$^{-34}$$\ \mathrm{J\cdot s}$$, $$c = 3.00 	imes 10^8$\ \mathrm{m/s})$$

Accepted Answer

$$1.8 	imes 10$$^{15}$$ photons

Question 8

Which phenomenon demonstrates the wave nature of light by producing a pattern of bright and dark bands?

Accepted Answer

Double-slit experiment

Question 9

Which transition in the hydrogen atom releases the greatest amount of energy?

Accepted Answer

From $$n=2 to$$ $$n=1$$

Question 10

A material has a binding energy of $$2.0 	imes 10$$^{-19}$$\ \mathrm{J}. If it is $$struck by photons of energy $$3.0 	imes 10$$^{-19}$$\ \mathrm{J}$$, what is the kinetic energy of the ejected electrons?

Accepted Answer

$$1.0 	imes 10$$^{-19}$$\ \mathrm{J}$$

Question 11

Which region of the electromagnetic spectrum has the highest photon energy?

Accepted Answer

Gamma rays

Question 12

What is the effect of increasing the frequency of light in the photoelectric effect experiment?

Accepted Answer

It increases the kinetic energy of the ejected electrons.

Question 13

Which of the following is true about the speed of electromagnetic waves in a vacuum?

Accepted Answer

All electromagnetic waves travel at the same speed, $$c = 3.00 	imes 10^8$\ \mathrm{m/s}.$$

Question 14

Which equation gives the energy of a photon?

Accepted Answer

$$E = h 
u$$

Question 15

If the wavelength of light is doubled, what happens to its frequency?

Accepted Answer

It is halved.

Question 16

Which of the following best describes the difference between radio waves and gamma rays?

Accepted Answer

Gamma rays have higher energy and shorter wavelength than radio waves.

Question 17

Which process is responsible for the dark lines observed in the absorption spectrum of hydrogen?

Accepted Answer

Electrons absorb photons and move to higher energy levels.

Question 18

A photon in the radio region has a frequency of $$5.0 	imes 10^8$\ \mathrm{Hz}. $$What is its energy?

Accepted Answer

$$E = 3.3 	imes 10$$^{-25}$$\ \mathrm{J}$$

Question 19

Which of the following is a real-world application of the emission spectrum of hydrogen?

Accepted Answer

Identifying elements in distant stars using spectroscopy.

Question 20

Which statement best describes the relationship between energy and wavelength for electromagnetic radiation?

Accepted Answer

Energy decreases as wavelength increases.

Atomic Spectra and Wave Behavior of Light: Study Notes

Study Guide - Practice Questions

Study Guide - Flashcards