$$\lambda = 3.78 \times 10$$^{-7}$$ m

$$1.09 \times 10$$^{15}$$ s$$^{-1}$$

$$E = -2.18 \times 10$$^{-18}$$ \left( \frac{1}{1^2$} - \frac{1}{2^2$} \right) J$$

Question 1

Which experiment led to the discovery of the electron and its charge-to-mass ratio?

Accepted Answer

Thomson's cathode ray tube experiment

Question 2

According to the Rutherford model, what is the main difference compared to Thomson's 'plum pudding' model?

Accepted Answer

Electrons orbit a dense, positively charged nucleus

Question 3

In the Bohr model, what determines the energy of an electron in a hydrogen atom?

Accepted Answer

The distance of the electron from the nucleus

Question 4

Which equation describes the relationship between the speed of light, wavelength, and frequency?

Accepted Answer

$$c = \lambda n$$

Question 5

A photon has an energy of $$5.25 	imes 10$$^{-19}$$ J. What is its wavelength in meters?

Accepted Answer

$$\lambda = 3.78 	imes 10$$^{-7}$$ m

Question 6

Which region of the electromagnetic spectrum does light with a wavelength of 275 nm belong to?

Accepted Answer

Ultraviolet

Question 7

What is the energy of a mole of photons with a frequency of $$6.34 	imes 10$$^{14}$$ s$$^{-1}$$?

Accepted Answer

$$253 kJ$$

Question 8

Which phenomenon cannot be explained by the wave model of light?

Accepted Answer

Photoelectric effect

Question 9

What is the minimum frequency required to eject electrons from molybdenum in the photoelectric effect?

Accepted Answer

$$1.09 	imes 10$$^{15}$$ s$$^{-1}$$

Question 10

If platinum begins to eject electrons at 195.7 nm, what is the kinetic energy of electrons ejected by 175 nm light?

Accepted Answer

$$1.20 	imes 10$$^{-19}$$ J

Question 11

Which transition in a hydrogen atom requires the greatest energy to be absorbed?

Accepted Answer

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

Question 12

What is the ionization energy of a hydrogen atom in the ground state?

Accepted Answer

$$2.1799 	imes 10$$^{-18}$$ J

Question 13

Which equation gives the de Broglie wavelength for a particle?

Accepted Answer

$$\lambda = \frac{h}{mv}$$

Question 14

When an electron in a hydrogen atom transitions from $$n=3 to$$ $$n=2$$, what type of electromagnetic radiation is emitted?

Accepted Answer

Visible

Question 15

What is the energy of a photon emitted during the $$n=2 to$$ $$n=1$$ transition in hydrogen?

Accepted Answer

$$E = -2.18 	imes 10$$^{-18}$$ \left( \frac{1}{1^2$} - \frac{1}{2^2$} ight) J$$

Question 16

Which series of hydrogen emission lines falls in the visible region?

Accepted Answer

Balmer series

Question 17

What is the maximum number of spectral lines that could be observed when hydrogen atoms are excited to the $$n=3$$ state?

Accepted Answer

3

Question 18

If an electron goes from $$n=1 to$$ $$n=3$$, was a photon absorbed or emitted?

Accepted Answer

Absorbed

Question 19

According to the Bohr Frequency Condition, what is the relationship between the energy difference and the frequency of the spectral line?

Accepted Answer

$$\Delta E = h n$$

Atomic Structure, Light, and Quantum Theory: Study Notes

Study Guide - Practice Questions