TG-1 Atoms 24-25

Please, select the correct statement:

• The atoms of a chemical element can have a different number of protons

• The atoms of a chemical element can have a different number of neutrons

• The cations of a chemical element have more electrons than protons

• The elements of the periodic table are arranged according to the number of electrons

The approximate wavelengths (in nm) of the RED and VIOLET colors are, respectively:

• 400 and 700

• 700 and 400

• 400 and 500

• 500 and 400

When analyzing the results of the photoelectric effect in Lithium, Sodium and Potasium, we observe that the threshold frequency (ν₀) values for these metals INCREASES in the following order:

• Li > Na > K

• Na > K > Li

• K > Na > Li

• K > Li > Na

Draw on a separate sheet the probability density of the particle in a one-dimensional box of size L for the state n = 1. The probability of finding the particle in this box when it is in its ground state is:

• Greater in the interval [0, L/4] than in the interval [L/4, L/2]

• Greater in the interval [L/2, 3L/4] than in [L/4, L/2]

• Equal in the interval [L/2, 3L/4] and [L/4, L/2]

• Less in the interval [L/2, 3L/4] than in [L/4, L/2]

Knowing that the expression for the Energy levels of an electron in a hydrogen-like atom is E_n = - hRZ²/n², h = 6.626x10^-34 J·s, R = 3.29x10¹⁵ s^-1 and 1 eV = 1.602x10^-19 J; the value of the third ionization energy of Li is:

• 13.6 eV

• 122.4 eV

• 54.6 eV

• 102.4 eV

All points located on the X-axis have the following values of θ and ϕ:

• θ = 0 and ϕ = 0

• θ = π/2 and ϕ = 0

• θ = π/2 and ϕ = π/2

• θ = 0 and ϕ = π/2

Choose the correct statement about the hydrogen-like atom:

• There are 4 orbitals in the electronic level with n = 2 and 6 orbitals in that of n = 3

• There are 9 degenerated orbitals in the electronic shell with n = 3

• The energy of the 3s and 3p orbitals is different

• For n = 3 and l = 2 , there are 4 different values of m_l = -2, -1, 1, and 2

The Rydberg constant has units of:

• Frecuency (Hz)

• Energy (J)

• Wavelength (m)

• Energy/time (J/s)

The work function (ϕ) in the photoelectric effect is related to the ionization potential (IP) of an atom in the following way:

• IP > ϕ

• IP < ϕ

• IP = ϕ

• IP = 125 ϕ

In the model of a particle in a one-dimensional box of size L, identify which of the following statements is correct:

• In the ground state, the wave function has a node at L/2

• In the ground state, the energy remains constant even if the length of the box is reduced by half (L/2)

• The kinetic energy of the particle in its ground state is greater than zero

• In the second energy level (n = 2), the wave function has two nodes