Quantum Numbers

What is the Rydberg constant?

1.097 * 10^7 m^-1

How many electrons are in one orbital?

2 electrons

How is the number of electrons in a shell determined?

2n^2

What are the possible elements for the following quantum numbers? n =2, l=1 n=3, l=0 n=5, l=3 n=4, l=2

2p elements: B,C,O,N,F,Ne 3s: Na, Mg 5f: Actinide 4d: Y, Zr, Nb, Mo, Tc, Ru, Rh, Pd, Ag, Cd

What happens to the energy levels of the first period of transition metals?

3d is at a lower energy than 4s so cations will be lost from 3d ex. Sc: [Ar]4s2 3d1

What is an orbital?

A region of space around the nucleus where an electron is likely to be found.

What is the exception to Hund's rule?

As d4 is considered unstable compared to d5 and d9 is unstable compared to d10, an electron is taken from 4s to fill up the fifth d orbital or tenth d orbital. ex. Cr: [Ar] 4s1 3d5 Cu: [Ar] 4s1 3d10

What is the electron configuration of Ca vs Ca2+?

Ca: [Ar] 4s1 Ca2+: [Ar]

Is the uncertainty principle related to the precision of the measuring instrument?

No, the principle is a property of nature; the electron is not actually a particle

When removing electrons to form cations, which electron is mainly removed?

The electron that has the highest energy is lost since easiest to remove to form the ion

What determines the absorption spectrum of a single atom?

The energy differences between ground-state electrons and higher-level electron orbits determine the frequencies of light a particular material absorbs.

What does the equation E(n) = E(1)/n^2 indicate?

The energy of the state of the electron

What is the Heisenberg's principle equation?

The product of the uncertainties in position and velocity is equal to or greater than a tiny physical quantity, or constant (h bar = h/(4π)) (deltax)(deltap) >_ h bar

Which of the following equations describes the maximum number of electrons that can fill a subshell? a) 2l+2 b) 4l+2 c)2l^2 d)2l^2+2

b) 4l+2

spdf refers to which quantum number?

linear momentum quantum number

Match the letters with its representing position of the electrons m(l) n m(s) l principal quantum number magnetic quantum number angular momentum quantum number spin quantum number

m(l): magnetic quantum number n: principal quantum number l: angular momentum quantum number m(s): spin quantum number

How can the number of orbitals in a given shell be determined?

n^2

What orbitals does a shell of n=3 have?

one s orbital, three p orbitals, and five d orbitals

Compare paramagnetic materials to diamagnetic materials.

paramagnetic: unpaired electrons that align with magnetic fields->attraction to magnet diamagnetic: all paired electrons, not easily aligned; repelled by magnets

What is the principal quantum number, linear momentum quantum number and magnetic quantum number for a p orbital?

principal: n =2 linear: l = 1 magnetic: m(l): -1, 0, +1 (3 different orientations)

What kind of orbital is it when n =1 and l=0?

s orbital

What does the Balmer series refer to?

series of spectral emission lines of the hydrogen atom that result from electron transitions from higher levels down to the energy level with principal quantum number 2

What is the idea that any orbital has a certain number of orientations in space refer to?

space quantization

An electron and tennis ball are both moving along the x-axis with a velocity of 50 m/s. IF the mass of the tennis ball is 0.058 kg and the velocity is measured to a precision of 0.02%, find the uncertainties in position of each object.

tennis: (delta x) (delta p) ~ h bar -> delta x ~ hbar/deltap->hbar constant/ 0.058 kg(0.002)(50m/s) = 1.82 * 10^-31 m electron: delta x ~ hbar/(9.11*10^-31kg * 0.002 * 50 m/s) = 1.16 * 10^-2 m This indicates that at a macroscopic level, uncertainty is more negligible than the uncertainty in the microscopic level

The principal quantum number (n) refers to

the energy level/shell the electron is found in; which gives an idea of the electrons distance from the nucleus

The magnetic quantum number refers to

the orientation of the orbital

The angular momentum quantum number refers to

the shape of the orbital

What does the spin quantum number indicate?

the two fundamental spin states of an electron in an orbital {either positive half or a negative half}

What is the Rydberg equation, which relates wavelength of light emitted to the orbital level change of an electron?

(1/λ) =R((1/nf^2) - (1/ni^2)) λ = Wavelength R = Rydberg's Constant (1.097⋅10^7) nf = Final Orbital Level ni = Initial Orbital Level

An electron within Hydrogen jumps from the second orbital to the first orbital. What wavelength of light is emitted considering that Rydberg's constant is 1.097⋅10^7? (A) 6.78⋅10^-4 (B) 1.22⋅10^-7 (C) 1.81⋅10^-9 (D) 8.43⋅10^-15

(B) 1.22⋅10^-7 (1/λ) =R((1/nf^2) - (1/ni^2)) (1/λ) =(1.097⋅10^7)((1/1^2) - (1/2^2)) (1/λ) = approx. (.75⋅10^7) 1/(.75⋅10^7) = λ 1.34⋅10^-7 = λ, which is closest to (B) 1.22⋅10^-7

Which is the symbol for the Spin Number? (A) l (B) n (C) m(l) (D) m(s)

(D) m(s) m(s) is the symbol for the Spin Number.

What are the values of the spin quantum number?

+1/2 (spin up) or -1/2 (spin down)

What is the range of the magnetic quantum number?

-l to +l

What is the range of angular momentum quantum number?

0, 1, 2... (n-1)

True or False According to the Heisenberg uncertainty principle, the position and momentum of a particle can be accurately measured at the same time

False. According to the Heisenberg uncertainty principle, the position and momentum of a particle cannot be accurately measured at the same time

True or False: Small changes in chemical structure only minimally impact light absorption and emission patterns.

False. Small changes, such as protonation and deprotonation, change in oxidation state or bond order, and others may cause dramatic changes in light absorption in a material.

What causes fluorescence?

It is a photon emission that occurs when an excited electron returns to the ground state through intermediate ground states. With smaller energy transitions than the initial energy absorbed, these materials can release photons of light in the visible range.

If l = 0, what would m(l) equal?

It would equal 0, because a sphere has only one orientation

Why is it that the position and momentum of a particle cannot be determined at the same time?

To accurately know the position of the particle, you need a low wavelength. However, this leads to a high momentum, making the electron move away and change the position of the particle.

During which electronic transitions is photon emission most common?

When electrons transition from a higher energy state to a lower energy state, they will experience photon emission.

What is the electron configuration of Sc+?

[Ar] 4s1 3d1

Which of the following is the correct electron configuration for Zn2+? a) 1s2 2s2 2p6 3s2 3p6 4s0 3d10 b) 1s2 2s2 2p6 3s2 3p6 4s2 3d8 c) 1s2 2s2 2p6 3s2 3p6 4s2 3d10 d) 1s2 2s2 2p6 3s2 3p6 4s0 3d8

a) 1s2 2s2 2p6 3s2 3p6 4s0 3d10

Which rule states that single electrons with the same spin must occupy each equal-energy orbital before additional electrons with opposite spins can occupy the same orbitals to minimize electron repulsion? a) Aufbau principle b) Hund's Rule c) Heisenberg Uncertainty Principle d) Pauli Exclusion Principle

b) Hund's Rule

Which of these following principles requires that an electron in the same orbital as another electron must spin in the opposite orientation? a) Aufbau principle b) Pauli Exclusion Principle c) Hund's Rule d) Electron Configuration Rule

b) Pauli Exclusion Principle Aufbau principle: in the ground state of an atom or ion, electrons fill atomic orbitals of the lowest available energy levels before occupying higher levels.

Which of the following electronic transitions would result in the greatest gain in energy for a single hydrogen electron? a) an electron moves from n=6 to n=2 b) an electron moves from n=2 to n=6 c) an electron moves from n=3 to n=4 d) an electron moves from n=4 to n=3

b) an electron moves from n=2 to n=6

The angular momentum quantum number for a p orbital would be? a) l=2 b) l= 1 c) l= 0 d) l= 1/2

b) l= 1

Which of the following quantum number sets is possible? a) n=2;l=2;m(l)=1; m(s) =+1/2 b) n=2; l=1; m(l) =-1, m(s) = +1/2 c) n=2; l=0; m(l)=-1; m(s) = -1/2 d) n=2;l=0;m(l)=1; m(s) = -1/2

b) n=2; l=1; m(l) =-1, m(s) = +1/2

Which of the following best explains the inability to measure position and momentum exactly and simultaneously according to the Heisenberg uncertainty principle? a) imprecision in the definition of the meter and kilogram b) limits on accuracy of existing scientific instruments c) error in one variable is increased by attempts to measure the other d) discrepancies between the masses of nuclei and of their component particles

c) error in one variable is increased by attempts to measure the other

Which principle states that any two electrons in a given atom cannot have the same 4 quantum numbers? a) Aufbau principle b) Hund's Rule c) Heisenberg Uncertainty Principle d) Pauli Exclusion Principle

d) Pauli Exclusion Principle

Ultraviolet light is more likely to induce a current in a metal than visible light. This is because photons of UV light: a) have a longer wavelength b) have a higher velocity c) are not visible d) have a higher energy

d) have a higher energy

Which of the following atoms only has paired electrons in its ground state? a) sodium b) iron c) cobalt d) helium

d) helium