# Quiz | Early Quantum Theory

Which one of the following types of radiation has the highest wavelength?

Visible light

Infrared light

Ultraviolet light

X rays

Wavelength:

X rays < UV light < visible light < IR light

Which one of the following types of radiation has the highest frequency?

Infrared light

Ultraviolet light

Microwaves

Radio waves

Wavelength:

UV light < IR light < microwaves < radio waves

c = λv ⇒ frequency is inversely proportional to the wavelength

⇒ Frequency:

UV light > IR light > microwaves > radio waves

What is the energy of one photon with a wavelength of 2.25 x 10^{-2} m?

4.97 x 10^{-44} J

8.83 x 10^{-24} J

1.13 x 10^{23} J

2.01 x 10^{43} J

E = $\frac{\mathrm{hc}}{\mathrm{\lambda}}$

h = Planck’s constant = 6.626 x 10^{-34} J.s

c = speed of light = 3.00 x 10^{8} m.s^{-1}

What is the frequency of radiation which has an energy of 1.52 x 10^{6} J per mole of photons?

1.38 x 10^{63} Hz

2.29 x 10^{39} Hz

3.81 x 10^{15} Hz

2.63 x 10^{-16} Hz

E = nhv

n = number of photons = 1 mol = 6.022 x 10^{23} photons

Which statement below is incorrect regarding early quantum theory?

Bohr’s model of the atom accounts for the absorption and emission spectrum of hydrogen atom

Bohr’s model of the atom accounts for the Rydberg equation

Energy states in the hydrogen atom are quantized

None of the above

What is the energy of one electron in the second orbital of a hydrogen atom?

-5.45 x 10^{-19} J

5.45 x 10^{-19} J

-1.83 x 10^{18} J

1.83 x 10^{18} J

E_{n} = $\frac{-2.1799\times {10}^{-18}}{{\mathrm{n}}^{2}}$

E_{n} = energy of the orbital n

n = number of the orbital = 2

According to the Bohr model for the hydrogen atom, how is the energy required to excite an electron from n=3 to n=4 compared to the energy required to excite an electron from n=2 to n=3?

Lower

Greater

Equal

Either equal or greater

$\frac{1}{{3}^{2}}$ - $\frac{1}{{4}^{2}}$ $<$ $\frac{1}{{2}^{2}}$ - $\frac{1}{{3}^{2}}$