Q: A photon of light has a wavelength of $$456\ \mathrm{nm}. $$What is its frequency?

$$6.58 \times 10$$^{14}$$\ \mathrm{Hz}$$

Q: Microwave ovens commonly use radiation with a frequency of $$2.45 \times 10^9$\ \mathrm{Hz}. $$What is the wavelength (in nm) of this radiation?

$$1.22 \times 10^8$\ \mathrm{nm}$$

Q: Calculate the energy (in joules) of a single photon with a frequency of $$7.5 \times 10$$^{14}$$\ \mathrm{Hz}.$$

$$4.97 \times 10$$^{-19}$$\ \mathrm{J}$$

Q: A sample of tungsten is irradiated with light of wavelength $$221.0\ \mathrm{nm}$$, causing electrons to be ejected with a speed of $$6.04 \times 10^5$\ \mathrm{m/s}. $$What is the work function $$W ($$binding energy) of tungsten? (Mass of electron $$= 9.10939 \times 10$$^{-31}$$\ \mathrm{kg})$$

$$7.74 \times 10$$^{-19}$$\ \mathrm{J}$$

Q: The work function of a metal is $$1.66 \times 10$$^{-17}$$\ \mathrm{J}. If $$the incident radiation has a wavelength of $$8.8 \times 10$$^{-9}$$\ \mathrm{m}$$, what is the kinetic energy of the ejected electron?

$$1.60 \times 10$$^{-17}$$\ \mathrm{J}$$

Q: Given the following energy levels for a hypothetical atom: $$E_4 = -1.0$$ \times $$10^{-19}$$\ \mathrm{J}$$, E_3$ = -5.0 \times 10$$^{-19}$$\ \mathrm{J}$$, $$E_2 = -1.0$$ \times $$10^{-18}$$\ \mathrm{J}$$, E_1$ = -1.5 \times 10$$^{-18}$$\ \mathrm{J}$$, what is the wavelength (in nm) of a photon needed to excite an electron from $$E_1 to$$ $$E_4$$?

$$1.60 \times 10$$^{3}$$\ \mathrm{nm}$$

Q: For the same hypothetical atom, what is the energy (in joules) a photon must have to excite an electron from $$E_2 to$$ $$E_3$$?

$$5.0 \times 10$$^{-19}$$\ \mathrm{J}$$

Q: When an electron drops from $$E_3 to$$ $$E_1 in $$the hypothetical atom, what is the wavelength (in nm) of the photon emitted?

$$1.24 \times 10$$^{3}$$\ \mathrm{nm}$$

Q: A proton is accelerated to a speed of $$2.90 \times 10^8$\ \mathrm{m/s} in a $$particle accelerator. What is its de Broglie wavelength (in nm)? (Mass of proton $$= 1.673 \times 10$$^{-27}$$\ \mathrm{kg})$$

$$1.36 \times 10$$^{-3}$$\ \mathrm{nm}$$

Q: A baseball has a mass of $$142\ \mathrm{g}$$ and a velocity of $$100.0\ \mathrm{mi/h} \pm 1.0\%. $$What is the minimum uncertainty in its position, $$\Delta x$$? ($$1\ \mathrm{mi} = 1609\ \mathrm{m}$$, $$\Delta x \cdot m \Delta v \geq \frac{h}{4\pi})$$

$$1.3 \times 10$$^{-34}$$\ \mathrm{m}$$

Question 1

A photon of light has a wavelength of $$456\ \mathrm{nm}. $$What is its frequency?

Accepted Answer

$$6.58 	imes 10$$^{14}$$\ \mathrm{Hz}$$

Question 2

Microwave ovens commonly use radiation with a frequency of $$2.45 	imes 10^9$\ \mathrm{Hz}. $$What is the wavelength (in nm) of this radiation?

Accepted Answer

$$1.22 	imes 10^8$\ \mathrm{nm}$$

Question 3

Calculate the energy (in joules) of a single photon with a frequency of $$7.5 	imes 10$$^{14}$$\ \mathrm{Hz}.$$

Accepted Answer

$$4.97 	imes 10$$^{-19}$$\ \mathrm{J}$$

Question 4

A sample of tungsten is irradiated with light of wavelength $$221.0\ \mathrm{nm}$$, causing electrons to be ejected with a speed of $$6.04 	imes 10^5$\ \mathrm{m/s}. $$What is the work function $$W ($$binding energy) of tungsten? (Mass of electron $$= 9.10939 	imes 10$$^{-31}$$\ \mathrm{kg})$$

Accepted Answer

$$7.74 	imes 10$$^{-19}$$\ \mathrm{J}$$

Question 5

The work function of a metal is $$1.66 	imes 10$$^{-17}$$\ \mathrm{J}. If $$the incident radiation has a wavelength of $$8.8 	imes 10$$^{-9}$$\ \mathrm{m}$$, what is the kinetic energy of the ejected electron?

Accepted Answer

$$1.60 	imes 10$$^{-17}$$\ \mathrm{J}$$

Question 6

A metal has a threshold frequency of $$2.84 	imes 10$$^{14}$$\ \mathrm{s}^{-1}. If $$light strikes the metal and ejects an electron with a kinetic energy of $$5.48 	imes 10$$^{-19}$$\ \mathrm{J}$$, what is the wavelength (in nm) of the incident light?

Accepted Answer

$$410\ \mathrm{nm}$$

Question 7

Using the Bohr model, what is the wavelength (in nm) of the photon emitted when a hydrogen atom transitions from $$n=5 to$$ $$n=2$$?

Accepted Answer

$$434\ \mathrm{nm}$$

Question 8

If a hydrogen atom had only 10 energy levels, how many lines would be observed in its emission spectrum?

Accepted Answer

$$45$$

Question 9

An electron in a hydrogen atom drops from $$n=7 to a $$lower energy level, emitting a photon of wavelength $$1006\ \mathrm{nm}. $$What is the final energy level of the electron?

Accepted Answer

$$n=4$$

Question 10

Given the following energy levels for a hypothetical atom: $$E_4 = -1.0$$ 	imes $$10^{-19}$$\ \mathrm{J}$$, E_3$ = -5.0 	imes 10$$^{-19}$$\ \mathrm{J}$$, $$E_2 = -1.0$$ 	imes $$10^{-18}$$\ \mathrm{J}$$, E_1$ = -1.5 	imes 10$$^{-18}$$\ \mathrm{J}$$, what is the wavelength (in nm) of a photon needed to excite an electron from $$E_1 to$$ $$E_4$$?

Accepted Answer

$$1.60 	imes 10$$^{3}$$\ \mathrm{nm}$$

Question 11

For the same hypothetical atom, what is the energy (in joules) a photon must have to excite an electron from $$E_2 to$$ $$E_3$$?

Accepted Answer

$$5.0 	imes 10$$^{-19}$$\ \mathrm{J}$$

Question 12

When an electron drops from $$E_3 to$$ $$E_1 in $$the hypothetical atom, what is the wavelength (in nm) of the photon emitted?

Accepted Answer

$$1.24 	imes 10$$^{3}$$\ \mathrm{nm}$$

Question 13

A proton is accelerated to a speed of $$2.90 	imes 10^8$\ \mathrm{m/s} in a $$particle accelerator. What is its de Broglie wavelength (in nm)? (Mass of proton $$= 1.673 	imes 10$$^{-27}$$\ \mathrm{kg})$$

Accepted Answer

$$1.36 	imes 10$$^{-3}$$\ \mathrm{nm}$$

Question 14

A baseball has a mass of $$142\ \mathrm{g}$$ and a velocity of $$100.0\ \mathrm{mi/h} \pm 1.0\%. $$What is the minimum uncertainty in its position, $$\Delta x$$? ($$1\ \mathrm{mi} = 1609\ \mathrm{m}$$, $$\Delta x \cdot m \Delta v \geq \frac{h}{4\pi})$$

Accepted Answer

$$1.3 	imes 10$$^{-34}$$\ \mathrm{m}$$

Question 15

What is the minimum value of the principal quantum number $$n$$ for an orbital in which $$m_\ell = -3$$?

Accepted Answer

$$n=4$$

Question 16

How many subshells are there in the shell designated by $$n=4$$? Name them.

Accepted Answer

4 subshells: $$4s$$, $$4p$$, $$4d$$, $$4f$$

Question 17

What is the total number of orbitals in the shell designated by $$n=5$$?

Accepted Answer

$$25$$

Question 18

Which of the following sets of quantum numbers is NOT permissible?

Accepted Answer

$$n=3$$, $$\ell=3$$, $$m_\ell=2$$, $$m_s=-1$$

Question 19

What is the maximum number of electrons that can be designated by the quantum numbers $$n=3$$, $$\ell=2$$?

Accepted Answer

$$10$$

General Chemistry Study Guide: Atomic Structure, Light, and Quantum Concepts

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