Which of the following is NOT isoelectronic with Ar? A) Cl-1 B) Ca+2 C) S-2 D) Rb+1 E) K+1

Which of the following is NOT isoelectronic with Ar? A) Cl-1 B) Ca+2 C) S-2 D) Rb+1 E) K+1
March 31, 2020 Comments Off on Which of the following is NOT isoelectronic with Ar? A) Cl-1 B) Ca+2 C) S-2 D) Rb+1 E) K+1 Accounting Assignment help

I) Multiple Choice (2 pts each)

1) Which of the following is NOT isoelectronic with Ar?

A) Cl-1 B) Ca+2 C) S-2 D) Rb+1 E) K+1


2) Which of the following is incorrect of electromagnetic waves and/or radiation?

A) The lower the frequency of electromagnetic radiation, the lower its energy.
B) All electromagnetic radiation travels at the speed of light, regardless of the energy associated with it.
C) High energy electromagnetic waves are associated with very long wavelength values.
D) The visible spectrum of electromagnetic radiation spans the wavelength region of 400 to 700 nm (the rainbow color portion of the spectrum).
E) An electromagnetic wave contains both electric and magnetic field components.

3) (a) Determine the ΔH°rxn for the following reaction: SiO2 (s) + 4 HF(g) → SiF4 (g) + 2 H2O(l)

ΔH°f SiO2 (s) = -910.9 kJ/mol; ΔH°f SiF4(g) = -1614.9 kJ/mol; ΔH°f H2O (l) = -285.8 kJ/mol, ΔH°f HF (g) = -273.0 kJ/mol

A) -716.8 kJ B) -183.6 kJ C) +1224.4 kJ D) +716.8 kJ E) +183.6 kJ









(b) Is this reaction endothermic or exothermic? Explain.





4) The element Neodymium, is an example of:

A) a representative element B) an actinide C) a transition metal D) a lanthanide E) a noble gas

5) Which of the following best describes certain group characteristics we discussed?

A) Some metal elements in Group 16 tend to exist in a +2 or +4 state.
B) Noble gases have the highest electron affinity of all the periodic elements.
C) Group 15 oxide compounds can form relatively strong acids upon reaction with water.
D) Halogens tend to have cleansing properties and their reactivity increases as one proceeds down the column.
E) The reactivity of Group 2 elements with water is much greater than the reaction of Group 1elements with H2O.

6) Which is of the following is true regarding Bohr’s Theory of electrons?

A) A photon is light is emitted when an electron moves from a higher to a lower state.
B) The highest energy state of a system is called the energized state.
C) Electron shells/orbits all have the same energy values associated with them.
D) Energy is absorbed as an electron moves from a higher state to a lower state.
E) The atomic spectrum for sodium is identical to the spectrum for lithium since they are both alkali metals.
7) Match the following descriptions with correct quantum number term.

____ This value determines the energy level of an electron’s orbit and is the average distance from the nucleus of an atom.
____ Represents the spatial distribution of electrons with subshells labeled s, p, d, f, etc.

____ This number describes the spatial distribution of an electron’s orbit based on the attraction and repulsion with other electrons and particles, and the number of orbitals or places for electrons to be paired in a subshell.


____ This is representative of whether an electron spin is pointed up or down

(a) magnetic quantum number, ml (c) principle quantum number, n


(b) angular momentum quantum number, l (d) spin quantum number, ms

8) Which of the following is not true of ionization energy and electron affinity?

A) The 2nd ionization energy is higher than the 1st ionization energy.
B) Ionization energy is the minimum energy needed to remove an electron from a gaseous atoms in its ground state.
C) Halogens tend to have low electron affinities.
D) It is easiest to remove an electron from elements with emptier valence shells.
E) Electron affinity is the negative of the energy change that occurs when an electron is accepted by an atom in the gaseous state to form an anion.

9) Which of the following is not true of thermochemistry and/or thermodynamics?

A) Energy cannot be created or destroyed, but can be converted or transferred from one form or another.
B) The change in the energy of a gaseous system can be determined by monitoring the expansion and contraction of that gas at constant pressure.
C) The system is the part of the universe that is of interest in a study.
D) Work is a not state function.
E) An endothermic process transfers thermal energy from the system to the surroundings.

II) True or False (1 pt each)

[T] [F] Chewing a piece of gum that contains 20 Calories is the equivalent of ingesting 2,000 energy calories.
[T] [F] Oxygen has a higher first ionization energy than Nitrogen.
[T] [F] Bomb calorimetry occurs at constant pressure.
[T] [F] Heat is the transfer of thermal energy between 2 bodies at different temperatures.
[T] [F] Halogens have high electron affinities and high ionization energies due their tendency to accept one electron.
[T] [F] Elements in Group 16 have the configuration ns2 np6 because they have six valence electrons.
[T] [F] The greater the n value in an atomic orbital, the lower the energy and the larger the orbital.
[T] [F] Amplitude is the distance between the crest of one wave to the crest of another, usually measured in m or nm.
[T] [F] The Aufbau principle distributes electronic energy levels from highest to lowest, with a 7p orbital having the lowest energy possible.
[T] [F] The reactivity of the elements in Group 1 increases upward with Lithium being the most reactive.
[T] [F] Br -1 has a smaller radius than Br.
[T] [F] An endothermic process absorbs energy such as the melting of water.
[T] [F] A d orbital can hold up to 10 electrons and is 4-leaf clover shaped.
[T] [F] Each orbital ml can only have a maximum of 2 electrons.
[T] [F] Enthalpy is used to quantify heat flow of a system in a process that occurs at constant pressure.
[T] [F] Energy is not a state function because it can be transferred or converted from one substance to another.
[T] [F] Dr. Hooper is a state champion clog dancer, mastering such steps as the High Horse and Cowboy Up. (free pt)
[T] [F] A substance with an endothermic ΔHsoln would be a useful material in a cold pack.
III) Fill in the Blank (1 pt per blank)

1) ____________________ energy comes from the sun and is earth’s primary energy source.
2) The _________________of _________________ is the heat generated or absorbed when a certain amount of solute dissolves in a certain amount of solvent.
3) The ___________________ __________________ is how the electrons are distributed among the various atomic orbitals in an atom.
4) When all electrons in the atomic orbitals are arranged in such a way that the net number of electrons are unpaired in a magnetic field (acts as a magnet), the substance is referred to as ______________________________.
5) The vertical distance from the midline of a wave to the peak or trough of a wave is its _______________________.
6) The _______________________ ______________________ Principle states that it is impossible to know both the momentum and the location of an electron or photon simultaneously.
7) The lowest energy electron shell/orbit of an atom are called its _______________________ state.
8) The energy stored within the bonds of chemical substances is ___________________ energy.
9) _________________ Law states that when reactants are converted to products, the change in enthalpy is the same whether the reaction takes place in one step or in a series of steps.
10) A particle of light is called a(n) ______________________ that moves in a wave-like pattern.
11) ______________________________ is the number of waves that pass through a particular point in one second.

IV) Free Response Questions Show All Work
1) A beaker contains 50.0 g of water at 21.5°C. How much heat is absorbed if the final temperature of the water is 67.2°C? The specific heat of water is 4.184 J/g°C. (4 pts)









2) (a) What is the energy change (in J) associated with an electron transition from an initial quantum state of 2 to a final quantum state of 4? Is energy absorbed or given off in this process? (3 pts)










(b) Calculate the frequency (in Hz) and the wavelength (in nm) associated with this radiation. (3 pts)









3) Write the correct electron configuration for the following species. (8 pts)

(a) Cs
(b) Te (entire configuration)
(c) Mn+4



(d) P -3



4) Calculate the standard enthalpy change for the reaction using the indirect method (4 pts)
Overall reaction: Ca (s) + ½ O2 (g) + CO2 (g)  CaCO3 (s) ΔHrxn = ??

step (1) : 2 Ca (s) + O2 (g) CaO (s) H1° = –1270.2 kJ/mol
step (2) : CaCO3 (s)  CaO (s) + CO2 (g) H2° = +178.3 kJ/mol













5) Why are the noble gases the least reactive group of elements, and why do they have the highest ionization energy of all elements? (4 pts)

















Bonus (2 pts): Circle which meme is funniest or most appropriate for this particular exam (It’s ok if none of them suit your sense of humor)

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