1610-CHEM I Final TopHat Questions- Ch. 2: Atomic orbitals: energy, shape, and electron density

How many angular nodes does a d_{yz} orbital have?

# ang. nodes = ℓ d-orbital => ℓ = 2 # ang. nodes = *2.0*

How many different f orbitals are there?

(2ℓ+1) = ? f-orbital => ℓ = 3 (2(3)+1) = *7.0*

*Which of the following orbitals can be represented by the set of quantum numbers (n = 4), (l = 1), (m_l = −1), (m_s = 1/2)?* A. 4d B. 4p C. 4s D. 1s

*Which of the following orbitals can be represented by the set of quantum numbers (n = 4), (l = 1), (m_l = −1), (m_s = 1/2)?* A. 4d *B. 4p* C. 4s D. 1s

*Which subshell is higher in energy?* A. 5p B. 6s

*Which subshell is higher in energy?* A. 5p *B. 6s*

*Match the quantum number with what the number represents.* 1. the overall shape of an orbital 2. the orientation of an electron with respect to a magnetic field 3. the orientation of an orbital in space 4. the distance of an electron from the nucleus

1. ℓ 2. m_s 3. m_ℓ 4. n

*Nitrogen has a 1s^{2} 2s^{2} 2p^{3} electron configuration. How many of nitrogen's electrons have ℓ = 1?*

3.0

*What would be the gravitational force (in Newtons) between a proton and an electron in a hydrogen atom? Use "E" for scientific notation. For example, the number 2.1 x 10^66 would be written as 2.1E6. Use 2 significant figures.*

3.6e-47 Use equation F=((m_1*m_2)*G)/(r^2)

What type of orbital does an electron with n = 3 and ℓ = 2 occupy?

3d or d

As n increases, the Bohr radius increases/decreases.

As n increases, the Bohr radius *increases*/decreases.

How many unpaired electron(s) does a carbon atom have in its ground state?

2.0

Calculate the energy, in joules (J), required to remove hydrogen's one electron from the ground state. This is known as hydrogen's ionization energy.

2.18e-18 J https://youtu.be/UwRfe2GiB0g

*Assume you each weigh 60 kg, what is the gravitational force (in Newtons)? Use two significant figures.*

2.4e-07 Use equation F=((m_1*m_2)*G)/(r^2)

Which orbital is the HOMO of a ground-state carbon atom?

2p

Which orbital is the LUMO of a ground-state carbon atom?

2p (has only 2 electrons in p orbital leaving the last p orbital empty)

*Determine which electron configuration is the excited state.* A. Oxygen - 1s^{2} 2s^{2} 2p^{4} B. Sodium - 1s^{2} 2s^{2} 2p^{6} 3s^{1} C. Chlorine- 1s^{2} 2s^{2} 2p^{6} 3s^{2} 3p^{5} D. Aluminum - 1s^{2} 2s^{2} 2p^{6} 3s^{2} 3p^{1} E. Magnesium - 1s^{2} 2s^{2} 2p^{6} 3s^{1} 3p^{1}

E. Magnesium - 1s^{2} 2s^{2} 2p^{6} 3s^{1} 3p^{1}

*Match the elements with the correct valence electron configurations.* 1. He 2. Be 3. C 4. P 5. V

1. 1s^2 2. [He]2s^2 3. [He]2s^2 2p^2 4. [Ne]3s^2 3p^3 5. [Ar]4s^2 3d^3

*Match the quantum numbers to the description.* 1. n 2. l 3. m_l A. Size and Energy of orbital B. Orientation of orbital C. Shape of the subshell D. Number of combined orbitals

1. A. Size and energy of orbital 2. C. Shape of the subshell 3. B. Orientation of the orbital

*Match the quantum numbers and the subshell (orbitals) in which electrons are found* 1. n=3 and l=2 2. n=2 and l=0 3. n=5 and l=1 A. 2s B. 3d C. 5p

1. B. 3d 2. A. 2s 3. C. 5p

*Rank the subatomic particles in order of increasing relative charge, with the smallest at the top and the largest at the bottom.* Electron, proton, neutron

1. electron 2. neutron 3. proton

*State # of Radial and Angular nodes for each orbital:* 1. 1s 2. 3p_z 3. 4d_xy 4. 6p_x

*1. 0 radial, 0 angular* total nodes: n - 1 n = 1 total = 0 *2. 1 radial, 1 angular* total nodes: n - 1 n = 3 total = 3 - 1 = 2 # ang. nodes = ℓ p-orbital => ℓ = 1 # ang. nodes = 1 # rad. nodes = (n-1) - ℓ = 1 3. *1 radial, 2 angular* total nodes: n - 1 n = 4 total = 4 - 1 = 3 # ang. nodes = ℓ d-orbital => ℓ = 2 # ang. nodes = 2 # rad. nodes = (n-1) - ℓ = 1 4. *4 radial, 1 angular* total nodes: n - 1 n = 6 total = 6 - 1 = 5 # ang. nodes = ℓ p-orbital => ℓ = 1 # ang. nodes = 1 # rad. nodes = (n-1) - ℓ = 4 https://youtu.be/wW27P3OCKNw

*Compared to the rest of an atom, which of the following describes the nucleus?* A. Smaller and contains most of the atom's mass B. Smaller and contains hardly of an atom's mass C. Larger and contains most of the atom's mass D. Larger and contains hardly of an atom's mass

*Compared to the rest of an atom, which of the following describes the nucleus?* *A. Smaller and contains most of the atom's mass* B. Smaller and contains hardly of an atom's mass C. Larger and contains most of the atom's mass D. Larger and contains hardly of an atom's mass

*The first maximum in the above graph of the radial probability distribution refers to what phenomenon.* 1st hump is smaller A. electrostatic repulsion B. electron penetration C. additional energy levels D. Pauli's principal E. orbital mixing

*The first maximum in the above graph of the radial probability distribution refers to what phenomenon.* 1st hump is smaller A. electrostatic repulsion *B. electron penetration* C. additional energy levels D. Pauli's principal E. orbital mixing

*The graph shows the radial probability distribution for the 1s orbital of helium and hydrogen. Which of the following describes the plot accurately and provides a reasonable justification of the trends observed?* 1 peak for each line: He 1s higher and closer to nucleus, H 1s lower and farther from nucleus A. He and H 1s orbitals have the same electron probability distribution and are of equal energy. B. The He and H 1s orbitals have different radial probabilities with the He 1s having a higher density closer to the nucleus. The orbital with the highest density (He) closest to the nucleus is more stable and lower in energy than H. C. The He and H 1s orbitals have different radial probabilities with the H1s having a higher density closer to the nucleus. The orbital with the highest density closest to the nucleus (H) has the higher energy. D. He and H 1s orbitals have the different electron probability distributions, but are of equal energy.

*The graph shows the radial probability distribution for the 1s orbital of helium and hydrogen. Which of the following describes the plot accurately and provides a reasonable justification of the trends observed?* 1 peak for each line: He 1s higher and closer to nucleus, H 1s lower and farther from nucleus A. He and H 1s orbitals have the same electron probability distribution and are of equal energy. *B.* *The He and H 1s orbitals have different radial probabilities with the He 1s having a higher density closer to the nucleus. The orbital with the highest density (He) closest to the nucleus is more stable and lower in energy than H.* C. The He and H 1s orbitals have different radial probabilities with the H1s having a higher density closer to the nucleus. The orbital with the highest density closest to the nucleus (H) has the higher energy. D. He and H 1s orbitals have the different electron probability distributions, but are of equal energy.

*What happens to the energy of an electron as it gets farther from the nucleus?* A. As an electron gets farther from the nucleus the principal quantum number goes up and the energy increases and the electron is less stable. B. As an electron gets farther from the nucleus the principal quantum number goes down and the energy increases and the electron is less stable. C. As an electron gets farther from the nucleus the principal quantum number goes up and the energy decreases and the electron is less stable. D. As an electron gets farther from the nucleus the principal quantum number goes up and the energy decreases and the electron is more stable.

*What happens to the energy of an electron as it gets farther from the nucleus?* *A. As an electron gets farther from the nucleus the principal quantum number goes up and the energy increases and the electron is less stable.* B. As an electron gets farther from the nucleus the principal quantum number goes down and the energy increases and the electron is less stable. C. As an electron gets farther from the nucleus the principal quantum number goes up and the energy decreases and the electron is less stable. D. As an electron gets farther from the nucleus the principal quantum number goes up and the energy decreases and the electron is more stable.

*What is the ground-state electron configuration of Cu^+ ? * A. [Ar]4s^2 3d^8 B. [Ar]4s^2 3d^10 C. [Ar]4s^1 3d^9 D. [Ar]3d^9 E. [Ar]3d^10

*What is the ground-state electron configuration of Cu^+ ? * A. [Ar]4s^2 3d^8 B. [Ar]4s^2 3d^10 C. [Ar]4s^1 3d^9 D. [Ar]3d^9 *E. [Ar]3d^10*

*What is the relationship between the energy of an orbital and its average radius?* A. As the radius increases, the orbital energy decreases. B. As the radius increases, the orbital energy increases.

*What is the relationship between the energy of an orbital and its average radius?* A. As the radius increases, the orbital energy decreases. *B. As the radius increases, the orbital energy increases.*

*What orbital type has the radial probability distribution in the above graph (Q02)?* Graph has 2 "humps" (peaks) A. 3d B. 2p C. 2s D. 4f

*What orbital type has the radial probability distribution in the above graph (Q02)?* Graph has 2 "humps" (peaks) A. 3d B. 2p *C. 2s* D. 4f

*Which ion is not isoelectronic with the others?* A. N^3- B. O^2− C. Ne^+ D. Al^3+ E. Mg^2+

*Which ion is not isoelectronic with the others?* A. N^3- B. O^2− *C. Ne^+* D. Al^3+ E. Mg^2+

How many electrons are needed to fill a complete set of d orbitals?

10.0

*Which of the following best describes the electron distribution that is represented by the principal quantum number n?* A. With an increase an n the probability of finding an electron further from the nucleus decreases. There is also a decrease in the number of regions in which the electron has little to no probability of localizing with an increase in n. B. With an increase an n the probability of finding an electron further from the nucleus increases. There is also an increase in the number of regions in which the electron has little to no probability of localizing with an increase in n. C. There is a continuous gradient in probability of finding an electron from the nucleus for all values of n. As n increases the probability of finding the electron further from the nucleus increases. D. There is a continuous gradient in probability of finding an electron from the nucleus for all values of n. As n increases the probability of finding the electron further from the nucleus decreases.

*Which of the following best describes the electron distribution that is represented by the principal quantum number n?* A. With an increase an n the probability of finding an electron further from the nucleus decreases. There is also a decrease in the number of regions in which the electron has little to no probability of localizing with an increase in n. *B.* *With an increase an n the probability of finding an electron further from the nucleus increases. There is also an increase in the number of regions in which the electron has little to no probability of localizing with an increase in n.* C. There is a continuous gradient in probability of finding an electron from the nucleus for all values of n. As n increases the probability of finding the electron further from the nucleus increases. D. There is a continuous gradient in probability of finding an electron from the nucleus for all values of n. As n increases the probability of finding the electron further from the nucleus decreases.

*Which of the following combinations of n and ℓ are not allowed?* A. n = 1 and ℓ= 0 B. n = 3 and ℓ = 1 C. n = 4 and ℓ = 0 D. n = 2 and ℓ = 2 E. n = 5 and ℓ = 3

*Which of the following combinations of n and ℓ are not allowed?* A. n = 1 and ℓ= 0 B. n = 3 and ℓ = 1 C. n = 4 and ℓ = 0 *D. n = 2 and ℓ = 2* E. n = 5 and ℓ = 3 https://youtu.be/9Oqb3P3FN0w

*Which of the following hypotheses summarizes the calculated atomic orbitals you compared in the Expo and the reactivity of potassium?* A. The energy of the HOMO reports on the stability of the element. The lower in energy the HOMO is the more stable the element is. B. The gap between the HOMO and LUMO reports on the stability of the element. The smaller the gap the less stable (more reactive) the element is. C. The gap between the HOMO and LUMO reports on the stability of the element. The larger the gap the less stable (more reactive) the element is. D. The energy of the LUMO reports on the stability of the element. The lower in energy the LUMO is the more stable the element is.

*Which of the following hypotheses summarizes the calculated atomic orbitals you compared in the Expo and the reactivity of potassium?* A. The energy of the HOMO reports on the stability of the element. The lower in energy the HOMO is the more stable the element is. *B.* *The gap between the HOMO and LUMO reports on the stability of the element. The smaller the gap the less stable (more reactive) the element is.* C. The gap between the HOMO and LUMO reports on the stability of the element. The larger the gap the less stable (more reactive) the element is. D. The energy of the LUMO reports on the stability of the element. The lower in energy the LUMO is the more stable the element is.

*Which of the following statements describe the arrangement and properties of the particles in an atom?* A. Neutrons and protons form the nucleus at the center of the atom. B. Electrons are arranged around the nucleus C. Electrons rotate around the nucleus. D. There is an attractive force between the negatively charged electrons and the positively charged nucleus.

*Which of the following statements describe the arrangement and properties of the particles in an atom?* *A. Neutrons and protons form the nucleus at the center of the atom.* *B. Electrons are arranged around the nucleus* C. Electrons rotate around the nucleus. *D. There is an attractive force between the negatively charged electrons and the positively charged nucleus.*

*Which of the following would be a the most informative comparison to investigate the reactivity of potassium?* A. K,K^-, and H B. K, K^+, and Ar C. K, N, and O D. K, K^+, and O

*Which of the following would be a the most informative comparison to investigate the reactivity of potassium?* A. K,K^-, and H *B. K, K^+, and Ar* C. K, N, and O D. K, K^+, and O

*Why did you pick the above series to compare?* A. These elements are known to be reactive and allow us to investigate the similarities between reactive elements. B. The potassium cation is stable and is most commonly observed species of potassium as it forms salts. Argon is the noble gas that is consider very stable (inert according to most textbooks) and is isoelectronic to the potassium cation. Therefore there are two stable species that can be compared to the highly reactive potassium metal. C. It doesn't mater what is compared because atomic orbital energies are not correlated with reactivity. All elements are stable and have equal reactivity. D. The simplest atoms are the only atoms that atomic orbital energies can be calculated for so we are restricted in the ones we can choose.

*Why did you pick the above series to compare?* A. These elements are known to be reactive and allow us to investigate the similarities between reactive elements. *B.* *The potassium cation is stable and is most commonly observed species of potassium as it forms salts. Argon is the noble gas that is consider very stable (inert according to most textbooks) and is isoelectronic to the potassium cation. Therefore there are two stable species that can be compared to the highly reactive potassium metal.* C. It doesn't mater what is compared because atomic orbital energies are not correlated with reactivity. All elements are stable and have equal reactivity. D. The simplest atoms are the only atoms that atomic orbital energies can be calculated for so we are restricted in the ones we can choose.

*Why does it become difficult to mathematically describe the Coulombic interactions in a multi-electron atom?* A. The negatively charged electrons will attract each other. B. The negatively charged electrons will cancel out the charge of the protons in the nucleus. C. Heisenberg's uncertainty principle makes it impossible to determine the exact location of the electrons. D. There are no equations to describe the Coulombic interactions between moving charges.

*Why does it become difficult to mathematically describe the Coulombic interactions in a multi-electron atom?* A. The negatively charged electrons will attract each other. B. The negatively charged electrons will cancel out the charge of the protons in the nucleus. *C. Heisenberg's uncertainty principle makes it impossible to determine the exact location of the electrons.* D. There are no equations to describe the Coulombic interactions between moving charges.

Click on the value of the radius on the x-axis you think the electron with an R_{2s} wave-function is most likely to be found.

The x-axis point (radius) where wave-function has highest peak

Which image best captures the shape of a 3p orbital? 1. Vertical dumbell 2. Reflected Mushrooms 3. Small reflected mushrooms with semicircles surrounding top and bottom

Which image best captures the shape of a 3p orbital? 1. Vertical dumbell *2. Reflected Mushrooms* 3. Small reflected mushrooms with semicircles surrounding top and bottom