Chapter 2

Which of the following electron transitions occurs in the ultraviolet range of the electromagnetic spectrum?

• n=3 to n=1

• n=3 to n=2

• n=4 to n=3

• n=2 to n=3

Which of the following electron transitions in the hydrogen atom has the highest frequency?

• n=3 to n=1

• n=4 to n=2

• n=5 to n=3

• n=7 to n=2

How many lines can be formed in the ultraviolet range for all the transitions involving the first seven energy levels in the emission spectrum for the hydrogen atom?

• 6

• 7

• 8

• 9

The emission spectrum of hydrogen atom is a line spectrum because

• energy is required to excite an electron

• electrons which are unstable will radiate energy

• an excited electron has a higher energy and is not stable

• the energy of an electron in a hydrogen atom is quantised

An excited electron residing in the energy level n=4 drops to n=1. What is the wavelength of the emission if the frequency is 3.09 x 10¹⁵ Hz?
[c = 3.00 x 10⁸ ms^-1]

• 4.69 x 10^-6 m

• 2.91 x 10^-7 m

• 3.88 x 10^-7 m

• 9.71 x 10^-8 m

Which of the following can be obtained from the Lyman series in the hydrogen atom spectrum?

• The ionisation energy of hydrogen

• The relative atomic mass of hydrogen

• The bond energy of hydrogen

• The vaporisation enthalpy of hydrogen