Problem 117
A 1000 watt radio transmitter operates at a frequen cy of \(880 \mathrm{kc} / \mathrm{sec}\). How many photons per sec. does it emit? \(\left[\mathrm{h}=6.626 \times 10^{-34} \mathrm{~J} \mathrm{~s}\right]\) (a) \(2.51 \times 10^{30}\) (b) \(2.27 \times 10^{28}\) (c) \(1.72 \times 10^{30}\) (d) \(1.77 \times 10^{27}\)
Problem 118
How many moles of electrons weigh one kilogram? (mass of electron \(=9.108 \times 10^{-31} \mathrm{~kg}\), Avogadro number \(\left.=6.023 \times 10^{23}\right)\) (a) \(6.023 \times 10^{23}\) (b) \(\frac{1}{9.108} \times 10^{31}\) (c) \(\frac{6.023}{9.108} \times 10^{54}\) (d) \(\frac{1}{9.108 \times 6.023} \times 10^{8}\)
Problem 120
Calculate the wavelength and energy of the radiation emitted for the electronic transition from infinity \((\infty)\) to stationary state first of the hydrogen atom. \(\left(\mathrm{R}_{\mathrm{H}}=1.09678 \times 10^{7} \mathrm{~m}^{-1}, \mathrm{~h}=6.6256 \times 10^{-34} \mathrm{Js}\right)\) (a) \(2.18 \times 10^{-21} \mathrm{~kJ}\) (b) \(3.18 \times 10^{-22} \mathrm{~kJ}\) (c) \(1.18 \times 10^{-23} \mathrm{~kJ}\) (d) \(2.18 \times 10^{-31} \mathrm{~kJ}\)
Problem 122
The wavelength of the radiation emitted, when in a hydrogen atom electron falls from infinity to stationary state one, would be (Rydberg constant \(\left.=1.097 \times 10^{7} \mathrm{~m}^{-1}\right)\) (a) \(91 \mathrm{~nm}\) (b) \(192 \mathrm{~nm}\) (c) \(406 \mathrm{~nm}\) (d) \(9.1 \times 10^{-8} \mathrm{~nm}\)
Problem 123
Which of the following sets of quantum numbers represents the highest energy of an atom? (a) \(\mathrm{n}=3, l=2, m=1, \mathrm{~s}=+1 / 2\) (b) \(n=4, l=0, m=0, s=+1 / 2\) (c) \(\mathrm{n}=3, l=0, \mathrm{~m}=0, \mathrm{~s}=+1 / 2\) (d) \(\mathrm{n}=3, l=1, \mathrm{~m}=1, \mathrm{~s}=+1 / 2\)
Problem 124
In a multielectron atom, which of the following orbitals described by the three quantum numbers will have the same energy in the absence of magnetic field and electric fields? (a) \(\mathrm{n}=1, l=0, \mathrm{~m}=0\) (b) \(\mathrm{n}=2, l=0, \mathrm{~m}=0\) (c) \(\mathrm{n}=3, l=1, \mathrm{~m}=1\) (d) \(\mathrm{n}=3, l=2, \mathrm{~m}=1\) (e) \(\mathrm{n}=3, l=2, \mathrm{~m}=0\) (a) \(\mathrm{b}\) and \(\mathrm{c}\) (b) \(\mathrm{d}\) and \(\mathrm{e}\) (c) \(\mathrm{c}\) and \(\mathrm{d}\) (d) a and b
Problem 125
Of the following sets which one does not contain iso electronic species? (a) \(\mathrm{PO}_{4}^{3-}, \mathrm{SO}_{4}^{2-}, \mathrm{ClO}_{4}^{-}\) (b) \(\mathrm{CN}^{-}, \mathrm{N}_{2}, \mathrm{C}_{2}^{2-}\) (c) \(\mathrm{SO}_{3}^{2-}, \mathrm{CO}_{3}^{2-}, \mathrm{NO}_{3}\) (d) \(\mathrm{BO}_{3}^{3}, \mathrm{CO}_{3}^{2-}, \mathrm{NO}_{3}^{-}\)
